I did this mod about a year ago, it has worked great and have gotten many questions about it, so here you go:

You can clearance the stock YJ plastic tank for an easy 4" stretch. I stretched the rear 4" running an 8.8 and still have about an inch or so clearance.
How did I do it? Here is a basic run down:
- The concept is to mold the plastic tank with a bubble in the center to clear the pumpkin (similar to genright design)
- The first step is to mod the gas tank skid so the pumpkin clears. I made a metal indention in the skid were the pumkin rides.
- I used a bad ass industrial heat gun to heat the front of the tank until it was too hot to touch. Basically got it as hot as I could with the heat gun. The tank is pretty thick and very durable (a carefully position propane torch would have worked too). With the fuel sending unit/pump out, there is ample room to heat from the inside as well.
- The next step is to put the tank in the modified skid while it is hot. I put the skid/tank assembly under the jeep and used a jack to provide downward pressure on the tank while I continued to heat. In fact I did this over a couple night span- heat-press together, etc. Think I even used some wratchet straps or what ever I could find to help pull it into the skid. Eventually it got in there enough to put the factory strap on over the top to hold it all together. I welded some all thread on the ends of the factory straps so I could sinch it together while again under heat.
- Got it all put back under the Jeep and all was well, not even close to hitting the diff, it still holds over 15 gallons and has had NO signs of leaks for over a year.
Notes on build:
- You can't get the tank hot enough for it to get really solft, this is some tough plastic. It takes alot of force to fit it in the skid plate.
- My bend goes all the way up to the internal fuel pump baffle inside the tank.
- Mod doesn't cost anything but takes some time and fabrication to complete (what doesn't). Now I have the tank under the body, full storage and a rear seat.

Putting a 14b in the weekend, and it looks like there is enough room with some minor trimming.

modified skid
http://i290.photobucket.com/albums/ll257/springb025/RodeoJeep028.jpg
Bubble in tank
http://i290.photobucket.com/albums/ll257/springb025/RodeoJeep027.jpg
Tank in skid
http://i290.photobucket.com/albums/ll257/springb025/UGH010.jpg
http://i290.photobucket.com/albums/ll257/springb025/UGH011.jpg
http://i290.photobucket.com/albums/ll257/springb025/UGH012.jpg
Tank in Heep
http://i290.photobucket.com/albums/ll257/springb025/RodeoJeep025.jpg
http://i290.photobucket.com/albums/ll257/springb025/RodeoJeep026.jpg

Wow, great job. Doing this would have never even occurred to me.

Dude . . . Fawking brilliant !! :smokin:
I dare say your a revolutionary.
How different (if any) are the TJ tanks ?

this is a damn good idea wish you posted this before i cut a giant hole in my floor. one thing you forgot to mention and i know is obvious but you did drain the gas right? and also how did you get rid of the fumes. i'm assuming this tank had to smell brand new on the inside before heating it for fear of it blowing up. awesome idea gotta say though:smokin:

awesome !!! one thing we use for gas removal is tide soap and water... wash and rinse and rinse and rinse...

Putting a 14b in the weekend, and it looks like there is enough room with some minor trimming.



Please make sure you let us know if the 14 bolt works.

I used to work in the petrolium field removing old gas station tanks, and to rid a tank of fumes just drain it as best you can and then drop in a bunch of dry ice. As the ice evaporates it will pull all of the gas fumes out of the tank. We even used to use gas powered cut off saws to cut the tanks up and never had a problem as long as we used dry ice in the tank.

...Now to find a used TJ tank and give this a try...

...Now to find a used TJ tank and give this a try...

theyre basically the same no change that i can see from mine to yours.

NICE!! Great idea man.

Anyone know if this would work with a poly tank on a CJ-7?

theyre basically the same no change that i can see from mine to yours.

When did the TJ go away from the gigantic nut holding the pump assembly in?

I think that might be of some concern as you need to get the pump in straight to get that nut back on, if the dent in the tank is too big or badly placed you could be in for a wrestling contest.

i used a torch on mine and got it soft enough to form the indentation with a mallet. you still need to do the inverted piece of steel on the skid plate as the indented plastic tank will eventually right itself with a full tank of gas.

Update: The 14b fit with a little gas tank skid modification. Luckily the indentation in the plasic tank was enough to clear the pumpkin.

We tried moving the 14b back another 1" on the perches and there was slight rubbing of the tank, could have made it work but didn't think it was worth the effort. If I was starting from scratch it could easily clear.

To summarize: Modified YJ tank, 4" rear stretch and a 14b clears easily, 5" it barely hits the tank.

When did the TJ go away from the gigantic nut holding the pump assembly in?

I think that might be of some concern as you need to get the pump in straight to get that nut back on, if the dent in the tank is too big or badly placed you could be in for a wrestling contest.

well i wasn't really looking at that but i would pull the big nut off take sending unit out put big nut on and go crazy. but as far as shape is concerned they're visually identical. another easier method to this i can see, would be if someone has access to a fairly large press. heat and press using your own "tank skid die" leave in there for a couple days with pressure and your good with a lot less beating and working.

will have to keep this in mind for the next build. I already cut the giant hole, made the skid and have my rear seat raised up so i think it is a little late for me.

I used to work in the petrolium field removing old gas station tanks, and to rid a tank of fumes just drain it as best you can and then drop in a bunch of dry ice. As the ice evaporates it will pull all of the gas fumes out of the tank. We even used to use gas powered cut off saws to cut the tanks up and never had a problem as long as we used dry ice in the tank.

...Now to find a used TJ tank and give this a try...

Thanks for sharring, sounds like an easy way to clear the tank.

Also, big thanks to the OP, I was planning on something like this soon for my build. This thread makes it easier to vizualize (sp?).

subscribed sharpmachine

I had thought abuot looking for a used TJ tank to try something like this on before I ruined mine. Can give up my back seat with the kid, dont want a fuel cell in the cab and can't afford a $900 Genright tank. This may be the solution.

Wow, what a find! I didn't know this existed! I'll be adding this to the Ultimate TJ thread and doing this mod myself when it comes time to stretch :D

I've sourced a used tank and skid for a TJ. I might also try an aftermarket skid to add some protection. If I get to try it out soon I'll post some pics.

Very sweet idea!

are you spring over or spring under?

pics of whole jeep please......:grinpimp:

What does "YIPIEE" mean:flipoff2:

Updates ? :flipoff2:

Nice tech :smokin:
I used to work in the petrolium field removing old gas station tanks, and to rid a tank of fumes just drain it as best you can and then drop in a bunch of dry ice. As the ice evaporates it will pull all of the gas fumes out of the tank. We even used to use gas powered cut off saws to cut the tanks up and never had a problem as long as we used dry ice in the tank.
Good info to know

Anyone know if this would work with a poly tank on a CJ-7?
Anyone try it on the Stock CJ 20 gallon tank?

I got my skid cut over the weekend and I should be draining my tank and starting to form it sometime this week/weekend. I'll try and get pics as I do this to a TJ tank.

updates on doing this to a TJ tank ? I'm planning to try it on the tank I have but be nice to hear some feedback/input first..

I'm just about finished with mine. Works just like the YJ tank setup pictured. The tough part is keeping the bottom of the tank flat while heating and dimpling the tank. I'll have to get some more pictures in the next couple of days.

Great thinking. I love it when ingenuity wins over spending money.

I beleive plastic gas tanks are lined with metal that is why they don't get soft when they get hot.
I'm not a 100% positive, but that is what my plastic welding instructor told me when I asked about making a plastic gas tank.

I beleive plastic gas tanks are lined with metal that is why they don't get soft when they get hot.
I'm not a 100% positive, but that is what my plastic welding instructor told me when I asked about making a plastic gas tank.

They aren't. Most any plastic tank made today is 6 layer co-extruded HDPE with approx 5mm wall thickness.
The layers are:
- outer HDPE layer (with black color)
- regrind layer (using ground up scrap tanks/leftovers)
- adhesive layer (very thin)
- EVOH layer (very thin hydrocarbon barrier layer)
- adhesive layer (very thin)
- inner HDPE layer (non-colored)

This is of course for Gasoline only, Diesel tanks do not require the barrier layer and can be only HDPE.
-troy

I'll have to get some more pictures in the next couple of days.

still waiting :shaking:

They aren't. Most any plastic tank made today is 6 layer co-extruded HDPE with approx 5mm wall thickness.
The layers are:
- outer HDPE layer (with black color)
- regrind layer (using ground up scrap tanks/leftovers)
- adhesive layer (very thin)
- EVOH layer (very thin hydrocarbon barrier layer)
- adhesive layer (very thin)
- inner HDPE layer (non-colored)

This is of course for Gasoline only, Diesel tanks do not require the barrier layer and can be only HDPE.
-troy

What about plastic fuel cells are they just straight HDPE?

still waiting :shaking:

I'm really sorry about that. I've been working mad overtime for the past month or so and haven't even gotten out to my garage. :homer: I haven't forgotten about it though... :grinpimp:

Here are those pictures of a TJ tank that has been modified. I finally got out to my garage to work on the Jeep and snapped some pictures while I was out there :D

In this picture you can see the dimple in the stock skid. I originally made it to fit around a D44, but now am going with a D60, so I may have to change the dimple a bit
http://i159.photobucket.com/albums/t123/mattamd_xp/Jeep%201%20ton%20swap/IMG_5740.jpg

I still have to heat the tank another time or two to get it to fit in closer to the skid. Right now it fits, but the tank is slightly distorted rather than completely conformed to the dimple. I have to take the tank out to heat it and to re-install the pump, so hopefully I'll remember to take pictures of that whenever I get to that point...
http://i159.photobucket.com/albums/t123/mattamd_xp/Jeep%201%20ton%20swap/IMG_5750.jpg

What about plastic fuel cells are they just straight HDPE?

I have only seen straight HDPE aftermarket fuel cells. Since they are not for OEM use, they don't have to conform to EPA or CARB 24 hour emissions cycling.

Awesome,,,,,,,,,,,,right on and all that!!

WHAT COMES TO MIND...WHY DIDNT I THINK OF THAT!!!!!!:eek::eek:

throw up some pics of the complete jeeps with this done (get and idea of stretch and ride height)
plz:p

This is beautiful. I was thinking of this very idea, but I scare myself sometimes with my own crazy ideas. It is real nice to see someone has already done it. Now my 14 bolt will fit into my YJ easily this weekend.

What about using a heat blanket like they use to bend large PVC conduit? It seems like you could just lay it on there for about ten minutes and then kneel on it.

Thoughts anyone?

This is beautiful. I was thinking of this very idea, but I scare myself sometimes with my own crazy ideas. It is real nice to see someone has already done it. Now my 14 bolt will fit into my YJ easily this weekend.

What about using a heat blanket like they use to bend large PVC conduit? It seems like you could just lay it on there for about ten minutes and then kneel on it.

Thoughts anyone?

Try it.
Take Pics.
Post Pics.
:flipoff2:
Sounds like a great idea :smokin:

Okay I am wanting to do this. BUT!!!! I am scared to death of blowing myself up! How are you guys getting rid of the fumes?

I read the part about dry ice but I can not even begin to think where I would source that!

How long would a tank have to sit before the fumes dissipated on there own?

What other ways to remove the fumes before heating are there?

Any grocery store should have dry ice. You will most likely have to ask for it as it'll be in the back.

Or you could fill the tank up with water.

you dont need dry ice and to go through all that. if you pull the pump out you should be able to work your arm in there and physically clean and wipe the inside of the tank. the fumes wont stay. once mine was really clean i threw a lit match in it. it sounds crazy, however the idea is to apply this in as controlled a situation as possible when you would be ready for a flame and not when you are sitting on top of it with a lit torch. with the tank empty and cleaned out, its not going to do much even if you do ignite some lingering fumes.

with the tank empty and cleaned out, its not going to do much even if you do ignite some lingering fumes.

True ,i cut open a junkyard tank to modify it and even with a grinder and some torch action the most i got was a little jet of fire out the filler next for a split second, and it had gas in it when i got it.

WOULD LIKE TO SEE MORE PICS OF THIS BEING DONE WITH TORCH PLEASE:grinpimp:

Just did mine on a TJ. What a pain in the butt! Probably one of the most time consuming and frustrating mod's I have done.... BUT.....

It worked flawlessly and saved me a grand!

I used a $25 wagner heat gun from lowes. So much better than try to use a torch. I heated until the plastic started smoking. That seemed to be the "moldable" point.

I have pics but I am too lazt to post em up.

Needless to say, but confirming this mod is very doable and a money saver....

Just be patient and be prepared to spend all day.

Picture of the completed stretch and are you spring over or under???? Please... I'm spring over , sooo do I really need to do this when I do the stretch???

Just did mine on a TJ. What a pain in the butt! Probably one of the most time consuming and frustrating mod's I have done.... BUT.....

It worked flawlessly and saved me a grand!

I used a $25 wagner heat gun from lowes. So much better than try to use a torch. I heated until the plastic started smoking. That seemed to be the "moldable" point.

I have pics but I am too lazt to post em up.

Needless to say, but confirming this mod is very doable and a money saver....

Just be patient and be prepared to spend all day.

..Then why'd you bother taking pics to begin with? Post em up.

I'll be doing one for a CJ as soon as the tank gets here. I'm gonna try Bardenk1's idea using the big ass press. I won't be too lazy to post pics afterwards. :flipoff2:

What this thread needs is pics of jeeps with modified tank installed and axle stretched back to give people a perspective of how much stretch they can expect to get with this mod.

Any of the people that have that completed got some side shot pics?

..Then why'd you bother taking pics to begin with? Post em up.

I'll be doing one for a CJ as soon as the tank gets here. I'm gonna try Bardenk1's idea using the big ass press. I won't be too lazy to post pics afterwards. :flipoff2:

What this thread needs is pics of jeeps with modified tank installed and axle stretched back to give people a perspective of how much stretch they can expect to get with this mod.

Any of the people that have that completed got some side shot pics?


Patience.... I'll post the pics of the tank mod And I pulled the rear dana 44 today and will be swapping in the Ford nine tomorrow and friday. when all is complete I will post. From the looks I can get 6 inches +

Patience.... I'll post the pics of the tank mod And I pulled the rear dana 44 today and will be swapping in the Ford nine tomorrow and friday. when all is complete I will post. From the looks I can get 6 inches +

I hope you're right. I'm gonna try to get 6" with a Sterling 10.25..
I'm fairly certain my tank's only gonna hold about 10 gallons when I'm done with it, hah.

Don't we all wish we could get another 6" :smokin:

Lookin forward to the pics, I have this one on the list of things to do when the axle swap/stretch goes down in a month or so.

I hope you're right. I'm gonna try to get 6" with a Sterling 10.25..
I'm fairly certain my tank's only gonna hold about 10 gallons when I'm done with it, hah.

Alot of it will depend on the truss you use and how its positioned. AND I imagine the axle will have to self clearance a little.

Alot of it will depend on the truss you use and how its positioned. AND I imagine the axle will have to self clearance a little.

That's good to hear too, since I'll be SOA with no truss.

Still working on the jeep. No pics. and no way I'm getting 6 inches. :shaking:

5 maybe. but again still working on it. just now making my control arms give me a day or two

:shaking: Gawddamnet :D
Pics :flipoff2:

is the skid and the sending unit the same for the plasic tank and the metal tank?
I am thinking I want to do this for my 90YJ but I have the metal tank

is the skid and the sending unit the same for the plasic tank and the metal tank?
I am thinking I want to do this for my 90YJ but I have the metal tank

I dont know for sure but I have a plastic tank I just removed from my 88YJ for someone to have.

I dont know for sure but I have a plastic tank I just removed from my 88YJ for someone to have.

Could you take a pic of the top so I coudl see were the sending unit goes in?

I be it would cost too much to ship that to Ohio :(

I am putting a 5.2L and 46rh in my yj. But I am stuck with about 13inch driveshaft. If I can get 3-4 inches this would be great. However I will have to carve up a kilby skid for this to work. Side shot of inches gained would be great

Could you take a pic of the top so I coudl see were the sending unit goes in?

I be it would cost too much to ship that to Ohio :(

ill take a photo today. I figured about the shipping cuz there a junkyard part, but you never know you or family might be passing this way.

Here is a pic of when we first finished rear stretch on 35s and an 8.8, 4" of stretch, TJ flares.
Jeep now has 39.5s and 14b, pictures to come one day in a build thread.
http://i290.photobucket.com/albums/ll257/springb025/Jeep%20Pics/Jeep016.jpg
front had waggy springs and offset perch for about 3", WB was about 100" and worked really well with 35s
http://i290.photobucket.com/albums/ll257/springb025/Jeep%20Pics/Jeep017.jpg

To the guys who did this with TJs, what did you do with the upper spring buckets? Pictures of the 4" stretch would be greatly appreciated.

Nevermind, figured it out.

Pictures of the TJs would still be cool though.

I started mine on my kilby skid today
http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279588488920.jpg
getting it welded up tomorrow

A trip to erock fabrication
http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279668359198.jpg
Almost finished product from the inside. (just need to grind the welds smooth and paint)
http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279672410429.jpg
And a look at the outside That faces the diff,
http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279672499732.jpg
What do you guys think?

A trip to erock fabrication
http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279668359198.jpg
Almost finished product from the inside. (just need to grind the welds smooth and paint)
http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279672410429.jpg
And a look at the outside That faces the diff,
http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279672499732.jpg
What do you guys think?

Looks fawkin cool. Off-roaders are all crazy bastards all that work to gain 5 inches of stretch.

Hey, for those that have done this-
What are the odds that I could mold it by heating it and parking a Jeep on it or pressing it with a hydraulic lift arm without ruining it? It's not gonna fit in the press I have after all and I'm gonna need more room than you guys seem to be achieving by beating on it..

Looks fawkin cool. Off-roaders are all crazy bastards all that work to gain 5 inches of stretch.

shoot i am doing it for 2inches.

I did this on my CJ-7 like six years ago. Got 5" stretch with a Dana 70 and 3" spring under lift.

I was "lucky" in that I had just ordered a new poly tank to replace my leaking steel tank so I didn't have to worry about fumes. I used an oxy-acetylene rig with a rosebud to heat the skid plate cherry red, then gradually formed it with a hammer. It got pretty thin in places, but made for nice round corners. Then I used the rosebud on the poly tank which was a little nerve wracking. When it felt soft and started to look wet as the torch passed over I dropped it into the skid and sat on it, heating the skid plate until it dropped into place and I could get the straps on.

Lost 2 gallons of capacity but I don't know how much of that was due to the poly tank.

I just finished this on a tj, I didnt go so extreme, just for a 1.5" stretch. Spring buckets are off, but they already were when I did the cv shaft and sye. Im going to correct it by cutting off the axle spring buckets and tilting them foreward.

I used a heat gun from the hardware store. I used the bottle jack and underneith the front bumper I put some pressure on the tank where I wanted to deform it (front edge) I heated it up and let it sit. Repeated with it jacked up a little more. Let it cool and removed it. The 2" dent was automatically there.

For the skid I cut two slots and BFH until I had the clearance I wanted.

Kinda a stealth stretch, but Im at 96" wb now.

I also raised the tank 1" while I was at it by cutting off the top edge and using some angle aluminum 1" lower.

Here are some pics of what I did. Not the best work but definatly functional.

http://i19.photobucket.com/albums/b200/rs4race/ea861e54.jpg
http://i19.photobucket.com/albums/b200/rs4race/e04c919a.jpg
http://i19.photobucket.com/albums/b200/rs4race/2711b66f.jpg
http://i19.photobucket.com/albums/b200/rs4race/af5d7a40.jpg

Part 2 of my kilby skid

Next step....

I washed the tank out and put probably put 120gallons of h2o through it. I then hesitantly dropped a match in it just in case since it still had that gas like smell. No flame time to get crackin.

Using a $9.99 cent heat gun from HF, I heated and got a dent going on the bottm. I then set in skid,stood on top and dropped a 16lb sledge appropriatley to force tank down. When it got to a point close to bottom I used a cheap ratchet strap to sinch down till I could get the strap nut started.

http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279755347778.jpg

I then moved the ratchet strap to the other side. Sinced down and got the other strap secure.

http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279756377020.jpg

Then the pic from the angle showing the clearance for the rear diff when I stretch the rear axle back 2inches

http://i975.photobucket.com/albums/ae233/drunkencityworker/img1279756385690.jpg

I have to say thanks again to jesse james for pointing out the idea for it and erock for dropping the beads on it.

And of cource pirate for being the sickest forum on the planet!

Brilliant work ^


Snagged this on CL for $60.
Both the tank & skid are in great shape !!
Hope to be cutting into it soon !!


http://i6.photobucket.com/albums/y231/stjjames/9ace61ef.jpg
http://i6.photobucket.com/albums/y231/stjjames/5fa50b10.jpg
http://i6.photobucket.com/albums/y231/stjjames/24224132.jpg

Update: The 14b fit with a little gas tank skid modification. Luckily the indentation in the plasic tank was enough to clear the pumpkin.

We tried moving the 14b back another 1" on the perches and there was slight rubbing of the tank, could have made it work but didn't think it was worth the effort. If I was starting from scratch it could easily clear.

To summarize: Modified YJ tank, 4" rear stretch and a 14b clears easily, 5" it barely hits the tank.



Thanks for the post. This'll help in my buddies build. Sticking a 14 bolt in with stock Wrangler springs (and a lovely traction bar, I'm sure). It MIGHT work how it is, but I'd feel better if the tank had a little clearance.

:DGreat Job on this post davev78, mylilyj :D:flipoff2:

I did this mod last year. I'll call it the Stuff ur Tank. I have a one inch body lift so I was able to move the fuel tank up into the frame nearly 2" just by cutting the stock skid down. As well as the aftermarket skid.
Easy to do. cut the mounting sections off of the stock skid (leaving 2-3" of material) bolt the cut off pieces back on the jeep loose. pry them open as you replace the tank with the lower half of the tank (use a floor jack under the tank). let them slip past one another untill the tank touches the body. Tack weld the stock skid in place, remove for final welding. Be sure and get your hoses attached before final install. I'll get more photos up of the skid when I do the mod in this thread for the stretch to 102" :flipoff2:
http://i297.photobucket.com/albums/mm210/mikegyver1/jeep/0124101727.jpg
http://i297.photobucket.com/albums/mm210/mikegyver1/jeep/0124101730.jpg
After
http://i297.photobucket.com/albums/mm210/mikegyver1/jeep/0128101808b.jpg
http://i297.photobucket.com/albums/mm210/mikegyver1/jeep/1102100948.jpg

Choppy chop chop :D

http://i6.photobucket.com/albums/y231/stjjames/9cf771f9.jpg

Melt, beat, strap

http://i6.photobucket.com/albums/y231/stjjames/093a3b03.jpg

Paint, sing & rejoice

http://i6.photobucket.com/albums/y231/stjjames/65781_1624003278435_1187090823_31558954_5087307_n. jpg

Sitting crooked, at 97".

http://i6.photobucket.com/albums/y231/stjjames/d8da7afa.jpg

Sweet i think i was around 97.5

Nice simple mod. Great looking job stjjames

i pulled a small vacuum on the tank
i thought that would make it super easy to make the bend for the hump i made i also used a heat gun and small propane torch

the vacuum took all the gas smell and dried it like nothin better no water needed was the only benifit cuz it made the bend great but also pulled the bottom of the tank all kinds of ways
well see if i can save it as im not done yet :mad3:

Using a Rokmen tank skid that I modded for extra clearance and this thread, I gained just about 2" of wheelbase on my 03 TJ. :smokin:

http://i276.photobucket.com/albums/kk29/fastfreak693/The%20Rubicon/PICT0163.jpg

http://i276.photobucket.com/albums/kk29/fastfreak693/The%20Rubicon/PICT0165.jpg

Its not the 5+ you get with a Gen-right/BTF tank but it was a hell of alot cheaper and did what I needed it to.

did anyone got 5" with d60 ?
should i'll give it a try or its worthless
what do you think guys ?
prorock d60 rear axle ?

I got 3" with a d44, could have gone 4" easy, maybe 5...

did anyone got 5" with d60 ?
should i'll give it a try or its worthless
what do you think guys ?
prorock d60 rear axle ?

I should be positioning my rear D60 this week after I get my doubler mounted, so I'll let you know. I'm really hoping for 3-5".

I should be positioning my rear D60 this week after I get my doubler mounted, so I'll let you know. I'm really hoping for 3-5".

Any luck with the stretch?

Ended up finding the BOM on my rear axle and it ends up being a D61 with 4.10's... Finally found a 14 bolt and then had to buy the wife a new car, so I still haven't gotten the rear installed. I did have the 14 bolt mocked in place last week, and with the front stretch I have from moving my steering box, I should end up around 99-100" with the stock tank dimpled. Hoping by the end of the month I'll have some free time to work on the Jeep again. Booked solid for the next week or two, so I'll try and update it when I finally get around to it.

Ended up finding the BOM on my rear axle and it ends up being a D61 with 4.10's... Finally found a 14 bolt and then had to buy the wife a new car, so I still haven't gotten the rear installed. I did have the 14 bolt mocked in place last week, and with the front stretch I have from moving my steering box, I should end up around 99-100" with the stock tank dimpled. Hoping by the end of the month I'll have some free time to work on the Jeep again. Booked solid for the next week or two, so I'll try and update it when I finally get around to it.


99-100 is easy w/o doing the tank and steering box move. I'm there now with waggy springs, a 14 bolt and 60. I'm shooting for 102-104" with the tank mod and steering box.

99-100 is easy w/o doing the tank and steering box move. I'm there now with waggy springs, a 14 bolt and 60. I'm shooting for 102-104" with the tank mod and steering box.

It is easy if you go higher with your ride height. -I'm running stock to lowered 1" from stock height on a TJ and just having lift from the tire diameter increase. Running the height I am without moving the steering box, the pitman arm ends up in the diff, literally. As it is, my tie rod is touching the pitman arm at full stuff :D Without the steering box and tank dimple, I'd probably be around 92" with the HP D60 front/14b rear. :laughing:

btw I'd love to see pictures of 100" wb without steering box move/astro box and a 14b in front of the tank

btw i'd love to see pictures of 100" wb without steering box move/astro box and a 14b in front of the tank

x2

X3

i was like a pig in shit when i found this thread ! thank you guys ! i picked up a yj on full widths 3 weeks ago and was not excited about telling the wife about the custom tank we'd have to get to put the tank back under the rear .

i cut my skid and molded the tank yesterday . mine looks like it will clear the 12b soa just fine in the rear . from what i understand from the PO it has a 8'' stretch in the wheel base total f&r but i dont know how far which way 102 '' total WB. id say at leat 4-5 in the rear . its running waggys up front and xj in the rear off the factory front hanger . on 37 km2 . im still a little new to all the jeep mods so dont light me up too bad ! im just posting for informational value

Finally got around to doing this mod. Biggest pain was getting the tank to sit low enough in the skid to keep the fuel lines from crushing agaist the body. A 1" body lift would have made it cake. But after multiple times of heating, beating, strapping, and test fitting its in there. Hoping for 4-5".
http://i56.tinypic.com/ekkl6b.jpg
Also got my corners cut.
http://i54.tinypic.com/33u972h.jpg
About where itll sit.
http://i56.tinypic.com/24wzhjq.jpg

I'm thinking of cutting my steel tank on my cj7 to get 4-5" more stretch just wondering if anyone has done it with good results. Thanks

3" rear stretch with tank mod.

35" tires, 2.5" lift, dana 44 rear, can get 1-2" if more maybe...

http://i15.photobucket.com/albums/a400/lake_v2/stretch.jpg

I forgot to post this up, but I met a guy the other day running a Camaro tank that already has the indent. He did have to fab up a skid for it though. I've got pictures somewhere if anyone's interested. Unfortunately I don't recall the year.

I forgot to post this up, but I met a guy the other day running a Camaro tank that already has the indent. He did have to fab up a skid for it though. I've got pictures somewhere if anyone's interested. Unfortunately I don't recall the year.

He'll yeah we're interested post them up.

20 gallon CJ tank, no stretch, just needed room for the Dana 60. 2-3"

http://i92.photobucket.com/albums/l8/mikeczj/Scrambler%20Build/DSC03878.jpg

He'll yeah we're interested post them up.

I guess he didn't do a skid at all.

608638

608639

I used to work in the petrolium field removing old gas station tanks, and to rid a tank of fumes just drain it as best you can and then drop in a bunch of dry ice. As the ice evaporates it will pull all of the gas fumes out of the tank. We even used to use gas powered cut off saws to cut the tanks up and never had a problem as long as we used dry ice in the tank.

...Now to find a used TJ tank and give this a try...

This doesn't actually remove the vapors - it just makes them harmless. The carbon dioxide from the dry ice sublimating purges all the oxygen from the tank. A similar effect could be had with a gas regulator and a tank of nitrogen.

I did something similar with my washer fluid tank (dinky, easy to bend, straight up HDPE) when I added a dual diaphragm booster to my MJ. Got out the plumber's torch, heated it up till it started looking slightly transparent, pushed it in with my thumbs, test fit, reheat, reform, repeat as needed, then filled it with washer fluid to cool it down and stiffen the plastic back up.

Worked great, never thought of using this method on a gas tank though.

If you want to clean the tank out before heating it, try swabbing or rinsing it with acetone. My usual degreasing/cleaning regime for light oils is to scrub with acetone, for heavy oils (gear lube, etc) I strip with gasoline and then rinse with acetone, works great. The gasoline dissolves the heavy gunk and the acetone washes off the gas quite well.

This doesn't actually remove the vapors - it just makes them harmless. The carbon dioxide from the dry ice sublimating purges all the oxygen from the tank. A similar effect could be had with a gas regulator and a tank of nitrogen.

I did something similar with my washer fluid tank (dinky, easy to bend, straight up HDPE) when I added a dual diaphragm booster to my MJ. Got out the plumber's torch, heated it up till it started looking slightly transparent, pushed it in with my thumbs, test fit, reheat, reform, repeat as needed, then filled it with washer fluid to cool it down and stiffen the plastic back up.

Worked great, never thought of using this method on a gas tank though.

If you want to clean the tank out before heating it, try swabbing or rinsing it with acetone. My usual degreasing/cleaning regime for light oils is to scrub with acetone, for heavy oils (gear lube, etc) I strip with gasoline and then rinse with acetone, works great. The gasoline dissolves the heavy gunk and the acetone washes off the gas quite well.

While it does purge all air from the tank, it also purges all the gasoline fumes due to the specific gravity of CO2 being higher than that of gasoline vapors (actually about twice that of gasoline). The CO2 sinks and fills the tank from the bottom purging out all fumes and other gases while replacing it with an inert gas that will not support combustion.

Lake_v2 You have any pitcures of the bubble and how much you notched the skid? I'm linking/stetching my yj 3" and trying to figure out if I can get this to work or have to buy a cell.

about midway down the page on this thread is the only pics i got of the tank/skid.

when i pulled mine out the skid was rusted through in the center, made a new skid out of 3/16" plate with the same bottom dimensions as the stock one.

I also found that I had to flip my sender/pickup 180* because the float was hitting the dimple and would not go back in.

http://www.infectiousoffroad.com/PHPBB3/viewtopic.php?f=5&t=1805

Here are the images for Lake_v2 Gas tank. :)

http://i1216.photobucket.com/albums/dd363/honeyduemelon/photo5.jpg
http://i1216.photobucket.com/albums/dd363/honeyduemelon/photo4.jpg
http://i1216.photobucket.com/albums/dd363/honeyduemelon/photo3.jpg
http://i1216.photobucket.com/albums/dd363/honeyduemelon/photo2.jpg
http://i1216.photobucket.com/albums/dd363/honeyduemelon/photo1.jpg

started messing with this today after looking at it/thinking about it for over a year.

the chinese ratchet straps Ive got werent up to the task. that or I was rushing.

The tank's been sitting for over a year, been rinsed a few times and I went at it with a heat gun, after cutting/welding a notch in an old stock skid I got for this purpose.

aside from the straps breaking, and my kid waking up I had another problem. if I pulled the tank DOWN over the hump, it kinked the bottom part of the tank, if I pulled it in (with the top of the tank up out of the back side of the skid bucket) it kinked the facing side... neither way really got a nice bump from the bottom corner of skid. does my rambling make any sense? the HF heat gun did a nice job of making the tank soft though...

Yes, makes Perfect sense. Mine did the same thing. I put a bottle jack and a 2x4 in sidenthe tank. Jacked the 2x4 against the inside top while heating them plastic. This pushed themtop of the tank back out and allowed me to install my fuel pump.

Of course this was after I had it strapped into the skid.

Does that make sense?

Yes, makes Perfect sense. Mine did the same thing. I put a bottle jack and a 2x4 in sidenthe tank. Jacked the 2x4 against the inside top while heating them plastic. This pushed themtop of the tank back out and allowed me to install my fuel pump.

Of course this was after I had it strapped into the skid.

Does that make sense?

OK, so you stuffed the tank into the skid, THEN flattened the bottom down with a jack? that makes sense... thanks for the reply! :)

Im gonna give this a try on my TJ, I am hoping for 5+ inches.
Just out of curiousity has any one figured out how much capacity is lost with this mod? It is irrelavent since the wife is really aginst losing the back seat.

OK, so you stuffed the tank into the skid, THEN flattened the bottom down with a jack? that makes sense... thanks for the reply! :)

Just read my post. I am on an Ipad and I have trouble hitting the "m" key instead of the space key. Just didn't want ya to think I am retarded!

Just read my post. I am on an Ipad and I have trouble hitting the "m" key instead of the space key. Just didn't want ya to think I am retarded!

I have an ipad and constantly do the same... mostly the n key though...

Im gonna give this a try on my TJ, I am hoping for 5+ inches.
Just out of curiousity has any one figured out how much capacity is lost with this mod? It is irrelavent since the wife is really aginst losing the back seat.

On my Yj tank I now have exactly 15.5 gallons capacity. towed jeep to gas station and filled it from bone dry.

Finally got my 14 bolt positioned with the rear tank installed. Sorry for the cell phone pictures it was all I had with me Sat when I did this. The first line is the hole in the frame at the top of the wheel arch. I'm 2.5" back from that on my centerline of the axle. I believe that would put me somewhere around 3" of stretch, and I could have gone back 2" more if I was running a slightly higher ride height (~2" higher and I could have gone back 2"). As it is at full stuff the front of the skid mounting surface is touching the top of the 14 bolt. It was enough to get me to 100" with the front stretch I did.

http://i159.photobucket.com/albums/t123/mattamd_xp/Jeep%201%20ton%20swap/IMG_20110903_122414.jpg

http://i159.photobucket.com/albums/t123/mattamd_xp/Jeep%201%20ton%20swap/IMG_20110903_122238.jpg

http://i159.photobucket.com/albums/t123/mattamd_xp/Jeep%201%20ton%20swap/IMG_20110903_122440.jpg

That's the first one I've seen with the notch actually contoured like the dife cover instead of just an inverted piece of the skid. Looks nice mattamd_xp.

I'm thinking of welding in 1/2 of a Dana 60 cover as my "patch piece" to make clearance for my 44 diff. Seems like the tank will conform better to the smooth rounded edges and I'll loose very little tank space.

That's the first one I've seen with the notch actually contoured like the dife cover instead of just an inverted piece of the skid. Looks nice mattamd_xp.

I'm thinking of welding in 1/2 of a Dana 60 cover as my "patch piece" to make clearance for my 44 diff. Seems like the tank will conform better to the smooth rounded edges and I'll loose very little tank space.

Thanks, I'm still in the fit up stage, so I haven't completely welded up the skid, but the tank conformed to the cutout very well and I didn't lose any more capacity than the notch itself takes. I'll probably end up making a 1/4" skid for it once I've finalized the notch. I first cut the notch when I was going to use a D44 rear, the 14 bolt center is offset to the driver side so I had to modify the notch a bit, but I really think it worked out well. :smokin:

So I went to the junkyard to get a camaro tank and they all have holes drilled in them how should i plug it if I get one?

Well, I just tried this last night with my factory CJ 20 gal tank. Cutting and welding the relief in the skid was no problem. I went to modify the plastic tank by heating it up with a propane (plumber's) torch. I started at the bottom. I got it hot and then tried to use a 2x6 piece of wood to make an indention. I must have gotten the plastic too hot because it melted and stuck to the wood. Results... hole in the plastic. :mad3: Looks like I'm the first to fuck this mod up.

Results... hole in the plastic. :mad3: Looks like I'm the first to fuck this mod up.
You're probably just the first to admit it.

I think the right method is a heat gun. Not a torch, especially not a blue flame. If anything, a rosebud tip.

even with a cheapo harbor freight heat gun I could see the plastic starting to soften too much in spots.

Thanks for the tips, I got leads on another tank... Going to practice on the old.

I'm getting ready to try this mod, would love to buy a GenRight tank but the $850 just isn't in the budget! I am looking to get a 4" strecth out of the rear with a spider 9. The axle is just brushing the tank in the stock location. So I am looking to make the 5" indent giving me a 1" clearence between the dif and the skid plate. My question is, has anyone ruin into any issues with a 5" indent with interfering with the sending unit and pickup?

Thanks!

I don't know if you will kit the pick up, but on a YJ tank there is a small aluminum tray fastened to the bottom of the tank. If you push to far in, you could pop this off and lose the benefits of the baffle.

Once you open the tank you should be able to tell how far you can go with it.

Not sure if you have a YJ, just putting this out there.

It's a YJ, that's interesting about the aluminum baffle, never knew there was anything like this in the tank.

For the YJ guys who did this mod, how far in did you indent the tank?

Update.
We had to redo mine.
I had folded the plastic over on the top too abruptly & developed a hole.

http://i6.photobucket.com/albums/y231/stjjames/1154d95e.jpg

We reshaped the frontside, sloping it in more, for a less abrupt angle & tighter fit around the diff.

http://i6.photobucket.com/albums/y231/stjjames/fac0cd29.jpg

And using my backup tank (incase I messed the first one up :D ) we hit it with a torch on the outside & a heat gun on the inside. Got it soft, shaping it with the flat edge of a dead blow hammer, rolling the shape into it & tossed it back in the skid. We kept heat on it & cinched down the compression straps to hold it in place. Took less than an hour this time around.

http://i6.photobucket.com/albums/y231/stjjames/32cc62de.jpg

And, the disposition of the old one.

http://i6.photobucket.com/albums/y231/stjjames/dd89b60d.jpg

Good to know, I'll be sure to take my time when I'm doing my tank next week :D

I'm finally getting around to doing this. I'm hoping to get at least 4" of stretch, 5" if possible. Using an 8.8 with Crane cover and a Warn tank skid. I got a harbor freight heat gun that I'll be using to heat up the tank. I think I've got the angle right on the skid to avoid busting a hole in the tank like Josh did :D

I actually used a torch when doing mine, was just very careful.

Thanks Lake. The HF gun actually worked pretty good. I heated up the tank tonight and molded it into shape then put it in the modified stock skid I have. I had made it before I picked up my Warn skid and it was a slightly larger cutout. This means when I put it in the Warn skid it should fit like a glove.

Overall it was very easy and didn't take long.

Thanks Lake. The HF gun actually worked pretty good. I heated up the tank tonight and molded it into shape then put it in the modified stock skid I have. I had made it before I picked up my Warn skid and it was a slightly larger cutout. This means when I put it in the Warn skid it should fit like a glove.

Overall it was very easy and didn't take long.



Nice!

Great mod, thanks for posting. I was wondering if this was possible. I have a cj5 thought I was stuck with the current axle location. I see a plastic tank in my near future.

Nice mod !!!

I will try it out on my Tj to gain some space for the Riddler cover on my 8.8!

Will post some pics!

http://farm8.staticflickr.com/7059/6865343861_53ca203690_z.jpg
D44 about 4.5" stretch
Its gonna be a tight one. Great Idea thanks for sharing.

Thanks Lake. The HF gun actually worked pretty good. I heated up the tank tonight and molded it into shape then put it in the modified stock skid I have. I had made it before I picked up my Warn skid and it was a slightly larger cutout. This means when I put it in the Warn skid it should fit like a glove.

Overall it was very easy and didn't take long.

this frustrates the shit out of me.

Ive tried this a couple different times, and still cant get it to fit together right :mad3:

What doesn't fit? Can you take some pics?

Did this on a friends rig. I liked using the propane torch myself.

On the pic above, make sure you don't leave those edges. Make a smooth transition so the tank does not abrade too this there. Ask sttjames how he knows...

The HF gun takes some time. I had it set up so I didn't have to hold it and it would warm up a particular section of the tank. Move it over, keep everything warm, and eventually it gets soft. Mold it into shape and I used cardboard against it so it wouldn't get punctured.

Did this on a friends rig. I liked using the propane torch myself.

On the pic above, make sure you don't leave those edges. Make a smooth transition so the tank does not abrade too this there. Ask sttjames how he knows...

I plan on making a panel with a roller

Thanks to this thread i did this mod on my Tj:


https://lh3.googleusercontent.com/-5BSRJIlwk1Q/TyWA1QBYJMI/AAAAAAAACQA/GWo3MNMZLRs/s640/IMG_2451.JPG


https://lh3.googleusercontent.com/-1XYWnNcseXk/TyWByVFoRqI/AAAAAAAACQw/x5sLMup7qj4/s512/IMG_2448.JPG


https://lh4.googleusercontent.com/-Xng73I9mOEU/TyWAzwKDqwI/AAAAAAAACP4/3WPZW_eCA9c/s640/IMG_2454.JPG

https://lh3.googleusercontent.com/-BqiPIbsgZIw/TyWA17IiwVI/AAAAAAAACQI/81oFctSK1BU/s640/IMG_2455.JPG

https://lh6.googleusercontent.com/-6uz5rjDg0go/TyWBV9-pgcI/AAAAAAAACQY/yqmj33FHFjA/s512/IMG_2458.JPG


https://lh4.googleusercontent.com/-ZBINrx2ldvI/TyWBarE8kgI/AAAAAAAACQg/fAuCWQvV5FM/s512/IMG_2461.JPG

https://lh6.googleusercontent.com/-XWfTwm1mf0A/TywmunYbp2I/AAAAAAAACRg/yIPcHKX_TEk/s640/2012-02-03_19-14-25_234.jpg

https://lh5.googleusercontent.com/-HOdDNvTmTms/Ty1wYbw-GTI/AAAAAAAACR8/9FUOGtwfxZ0/s640/IMG_0244.JPG

https://lh3.googleusercontent.com/-vkSz0JotM9w/Ty1wYsW_ksI/AAAAAAAACSA/iofMbA3SHRo/s640/IMG_0242.JPG

I wonder if anyone has done one of the aluminum skids this way yet.

I tried this mod today and it seemed to go pretty well after I decided to use my torch instead of my heat gun. I got the tank in the skid and went to install it in the jeep, and the top of the tank seems to hit the front crossmember :mad3: Has anybody had this problem? do I need to heat it up some more and try it again. Its only about a 2" deep notch.
http://i1220.photobucket.com/albums/dd452/sethcrae/jeep%20pics/jeeptankmod1.jpg
http://i1220.photobucket.com/albums/dd452/sethcrae/jeep%20pics/jeeptankmod2.jpg

Looks like the tank isn't sitting deep enough into the skid.

I picked up a small propane torch from Lowes today ($25) so I'll give that a shot. If I had more patience I would use two of the cheapo HF guns ($7 with coupon...worth it!).

I'll post pics when I'm done.

Looks like the tank isn't sitting deep enough into the skid.

I picked up a small propane torch from Lowes today ($25) so I'll give that a shot. If I had more patience I would use two of the cheapo HF guns ($7 with coupon...worth it!).

I'll post pics when I'm done.

the only problem I was having with the torch is the propane kept freezing up on me and cutting out when you do it for a long peroid of time. I may have to bug a buddy to come over and we will hit it with two torches and see if we cant get it to sit lower in the skid.

I wonder if anyone has done one of the aluminum skids this way yet.


This is aluminium:

https://lh6.googleusercontent.com/-XWfTwm1mf0A/TywmunYbp2I/AAAAAAAACRg/yIPcHKX_TEk/s640/2012-02-03_19-14-25_234.jpg :smokin:

This is aluminium:

https://lh6.googleusercontent.com/-XWfTwm1mf0A/TywmunYbp2I/AAAAAAAACRg/yIPcHKX_TEk/s640/2012-02-03_19-14-25_234.jpg :smokin:

NICE JOB.

:smokin:

I had issue with bubble popping up at bottom with straps on. I shortened the sending unit a bit then with skid strapped I inverted a 2 jaw bearing piller and Hung tank and skid by the opening and heated around the opening and it stretched up. Upon install I did a one inch body lift to make fit.

sent from the darkside of the moon

I smashed my tank yesterday. I got a couple creases/fold s in the plastic. It holds water overnight. will it screw me down the road?

Well the tank mod turned out to be a bigger pain in the a$$ than I originally thought, but its in. I was having troubles with it sitting to high in the skid not allowing me to install it in the jeep. I had my dad help me heat it up again and we strapped it into the skid it fit like a glove this time, but created a bubble (hump) at the bottom of the tank. So with it installed in the skid we heated the bottom again from the inside got it nice and soft then used a bottle jack and 2x4 under the hitch and pushed a dimple back in the bottom. Now with all that work I still had to modify my pickup tube I cut a half inch off and slightly bent it and reinstalled the screen and it finally fit in the bottom of my tank. All in all I spent about 3.5hrs working on the tank, so all it cost me was my time and some welding wire. The axle is installed and the jeep is sitting on its own weight once again just need to fill diff with oil, bleed brakes, and fill er up with some gas( which will be the most expensive part of the swap.)

I smashed my tank yesterday. I got a couple creases/fold s in the plastic. It holds water overnight. will it screw me down the road?

We did this to a friend's and it started leaking.

Well the tank mod turned out to be a bigger pain in the a$$ than I originally thought, but its in. I was having troubles with it sitting to high in the skid not allowing me to install it in the jeep. I had my dad help me heat it up again and we strapped it into the skid it fit like a glove this time, but created a bubble (hump) at the bottom of the tank. So with it installed in the skid we heated the bottom again from the inside got it nice and soft then used a bottle jack and 2x4 under the hitch and pushed a dimple back in the bottom. Now with all that work I still had to modify my pickup tube I cut a half inch off and slightly bent it and reinstalled the screen and it finally fit in the bottom of my tank. All in all I spent about 3.5hrs working on the tank, so all it cost me was my time and some welding wire. The axle is installed and the jeep is sitting on its own weight once again just need to fill diff with oil, bleed brakes, and fill er up with some gas( which will be the most expensive part of the swap.)

I had something similar happen. Let me know how it goes for you.

We did this to a friend's and it started leaking.

Yeah I saw that picture. How bad was his fold? I thought his ripped because he just shoved it in there and the way it was folded made it tear? :confused:

I had something similar happen. Let me know how it goes for you.

Headed out to the garage right now to fill her up with five gallon can. I will let you know how it goes. I'm sure my gauge will be off now too. I probably cant run it to close to empty now either oh well just carry an extra gallon or two with me at all times.

After reading the entire thread now I'm gonna have to to this!!!
great job guys!!

Any thoughts or knowledge about a truss on a dana 44 interfering with the gas tank mod?