I don't know much of anything about t-cases but need a doubler bad. Anyone know of a build tread or walk through on how to build one. Or have one for sale. Adding ford axles soon and they only have 4.10s.

How about you use the search function.. lots of info :flipoff2::mad3:

So why not regear the axles? what makes you think you "need" a doubler? its going to be a lot more work to run a doubler than it would to just regear the axles.

To answer in part:

a doubler is when you run two transfer cases back to front. it allows you to use the first transfer case's 4 low setting as a gear reduction, commonly referred to as a crawl box. In your case assuming you have a cherokee, you could run, after some serious work, the front half of the 231 as your crawlbox, basically saving the case and planetary gear reduction. Then you could run a second 231 or more commonly a dana 300. This allows you to select high or low on the first case, and you can select 2wd, 4wd, 4wdlow on the second case giving you 4 different gear reductions. With a dana 300 you can "twin stick" it to allow you to disengage the rear axle as well.

Some things to consider if you want to run a doubler:

You may need to modify both the front and rear driveshafts.
You'll need to modify the transfer cases, or purchase an already assembled setup.
You'll need to create a new mounting structure in order to support the added wieght.
You'll need to possibly modify the floor structure depending on the setup you want to run.

In summary, if you can get away with just regearing the axles do it, its doing to be cheaper and less work. ohh and as stated above, non of this is new information and could have easily been found with a search...

http://www.pirate4x4.com/forum/showthread.php?t=577021
http://www.pirate4x4.com/forum/showthread.php?t=754931

google "231/300 box for rocks build thread for dumbasses"

and the doubler is WAY cheaper than regearing....

you dont even need to sirtch, go to the second page in this section and look for the thread labeled doubler writeup for dummies, not too hard to find hell it even has your name right on it:flipoff2:

or you can click the first link i posted.... :shaking:

how is the doubler cheaper than regearing?
cost of a set of gears and install pack is about $200-300 per axle so lets just say $600.

Cost of a dana 300 is between $200-300.
Cost of shifters anywhere from $130 - $180.
Cost of dana 300 clocking ring $100 - $150.
Cost of Backing plate - lowball guess of $50.00
Cost of intermediate shaft - lowball guess of $50.00

just these parts put it at $530 - $730.

So they are in the same ball park. This is not taking into account material needed to make a new crossmember, driveshafts, misc....

If i made a mistake here in my logic please let me know. i just dont see how running a doubler is WAY cheaper than doing gears...

your close...


D&D makes a kit.. $515 bucks..

GreatWhite is also starting to produce these kits, minus the intermediate shaft which can be purchased separately from Duffy at D&D for $270 bucks i think...

the jeep already has a 231 in it.. and i bought my 300 for $100 bucks and rebuilt it for another $100...

i built my shifters with subaru shift cables from the U-pull it yard


so what are we really looking at here?? I'm at $715 with my set up.. but i also built my own shafts which had to be done anyway cuz i stretched the front and the rear..
this set up would be SUBSTANTIALLY stronger, lower crawl, and would leave room for upgrading in the future vs throwing money away regearing factory axles..

He needs a "Walk Trough on Duoblers"... And spelling I see.

He needs a "Walk Trough on Duoblers"... And spelling I see.

hahahahaha :smokin:

Dam thought this tread died with the first reply. Ok I can't spell for shit so sorry. I rely on spell check and that word looks funny right there. Any way plans for the build is to put my ford D44 and D60 under it with 410s and Detroit's. Also in the planes are 38 or bigger tires, coil overs, a full frame replacing the sheet metal one, and a body lift just to say FU to people on Cherokee form. Alot of work I know but with my skill level possible and its what I want. I use to work at a junk yard so I still have connections. My axles for example were free. Much cheaper to do a dubber for me. And I have to get new drive shafts any way. My first caged and chopped Xj I sold on here to a member. Going a different direction. Mainly bigger. Problem I don''t know t-cases at all never had one apart yet. Another problem all the good deals seam to be in CA. I appreciate all input. Thanks.

There's so much wrong with what you just said i don't know where to begin....

Body lift?? 38's on a 44 = Boomtime! If your going to be running anything over a 36" tire just run a 60 because you'll probably want more tire in the future, especially if your going to be running a doubler. You can build and build and build the 44 but when it comes down to it, its still a 44 and a dana 60 gives you more strength out of the box with upgrade options down the road. I think you should do a little bit more research on what you want, check out this thread as it pertains to lots of lift, there is good discussion/flaming in there about it.

http://www.pirate4x4.com/forum/showthread.php?t=705961

Did some research and the full frame and body lift are out. The 44 I don't want to use but have. Would now like a 60 with 4.10s but JY buy me wants 900 so will have to find a better deal.

http://www.rockhardxj.com/viewtopic.php?f=2&t=1686

If you REALLY want 38's, then man up and buy the 60. The 44 just DOES NOT have it to run 38's with a doubler.

And there is always room to grow afterwards.

im headed to get an '84 chevy K30 with the intent on parting it out...

you can call dibs if you'd like..



you know the number

A doubler also gives you the ability to keep your highway cruising speed the same while having a double low for crawling. Not too many people daily drive vehicles with doublers but just throwing it out ther for the dual purpose vehicle.

I went the route of a doubler vs. regearing the axles as it was cheaper for me since I was stretching everything anyways and tucking the belly as it was so a new crossmember and d shafts were coming anyways(built both by myself anyways). Also allowed me to keep the stronger 4.10 gear set in the axles vs. going with super small pinion gears. I still drive mine on the street as its an Antique too so it just made sense to buy a used doubler.

how is the doubler cheaper than regearing?
cost of a set of gears and install pack is about $200-300 per axle so lets just say $600.

Cost of a dana 300 is between $200-300.
Cost of shifters anywhere from $130 - $180.
Cost of dana 300 clocking ring $100 - $150.
Cost of Backing plate - lowball guess of $50.00
Cost of intermediate shaft - lowball guess of $50.00

just these parts put it at $530 - $730.

So they are in the same ball park. This is not taking into account material needed to make a new crossmember, driveshafts, misc....

If i made a mistake here in my logic please let me know. i just dont see how running a doubler is WAY cheaper than doing gears...

How? Your way off on axle gearing prices. My 14 was geared when I pulled it, but just to buy geasr and master install was $358 for the 60. Now I know how to install gears but most or a lot...do not. Therefore depending on if you have a good friend who likes beer or if you have to have a local shop set them up you could be looking at up to 600 for an axle regear. So just for the shits...think in terms of having to pay top price for install on both axles. You could easily surpass 1000 in no time.

D300...$200 Bucks.
231...should already have.
Shiters....make em.
Doubler plates and clocking ring...make em.
Mid shaft...265.
That puts my doubler cost near 500. (Thats complete and ready.)

Now your argument with the crossmember makes no sense. Yea you prolly wana beef it up regardless, but a stock crossmember has no affect at all on doubler vs non doubler. The crossmeber would depend more on suspension design and potential doubler support. But really...where talkin like 50 bucks material.

As for driveshafts, the op is doing axle swaps. So redoing driveshafts is mandatory anyways. Even if the OP kept a stock 231, the pinion lengths change with his axle swap so shortening the shafts would be required regardless. (Well...probably.)

your close...


D&D makes a kit.. $515 bucks..

GreatWhite is also starting to produce these kits, minus the intermediate shaft which can be purchased separately from Duffy at D&D for $270 bucks i think...

the jeep already has a 231 in it.. and i bought my 300 for $100 bucks and rebuilt it for another $100...

i built my shifters with subaru shift cables from the U-pull it yard


so what are we really looking at here?? I'm at $715 with my set up.. but i also built my own shafts which had to be done anyway cuz i stretched the front and the rear..
this set up would be SUBSTANTIALLY stronger, lower crawl, and would leave room for upgrading in the future vs throwing money away regearing factory axles..

YOUR close....:flipoff2: :laughing:

Duff's is $525 shipped.

And yes, with enough intrest, I intend to be a new 231/300 vendor and will be about 100 cheaper. And my kit will be 100% CNC machined all 6061. Only the first 20 or so orders would be without the midshaft. Once I make enough to order shafts in bulk I will offer complete kits. Price is uncertain but Im hoping for 430 shipped.

Dam thought this tread died with the first reply. Ok I can't spell for shit so sorry. I rely on spell check and that word looks funny right there. Any way plans for the build is to put my ford D44 and D60 under it with 410s and Detroit's. Also in the planes are 38 or bigger tires, coil overs, a full frame replacing the sheet metal one, and a body lift just to say FU to people on Cherokee form. Alot of work I know but with my skill level possible and its what I want. I use to work at a junk yard so I still have connections. My axles for example were free. Much cheaper to do a dubber for me. And I have to get new drive shafts any way. My first caged and chopped Xj I sold on here to a member. Going a different direction. Mainly bigger. Problem I don''t know t-cases at all never had one apart yet. Another problem all the good deals seam to be in CA. I appreciate all input. Thanks.

Replacing a unibody frame just to say "FU" to other forums and people is stupid as piss.

T cases are easy. That is if you can effectivly use a wrench, snap ring pliers and in some cases...a press.

oh blow me over your 10 bucks.. haha

I like doing things not to many other people have that was the idea of the body lift and frame. On the other forms I was on no one had done it. Here I found people who have. But if doing some thing you don't think no one else is doing is dumb as piss to you I really don't give a shit. :flipoff2:

How? Your way off on axle gearing prices. My 14 was geared when I pulled it, but just to buy geasr and master install was $358 for the 60. Now I know how to install gears but most or a lot...do not. Therefore depending on if you have a good friend who likes beer or if you have to have a local shop set them up you could be looking at up to 600 for an axle regear. So just for the shits...think in terms of having to pay top price for install on both axles. You could easily surpass 1000 in no time.

D300...$200 Bucks.
231...should already have.
Shiters....make em.
Doubler plates and clocking ring...make em.
Mid shaft...265.
That puts my doubler cost near 500. (Thats complete and ready.)

Now your argument with the crossmember makes no sense. Yea you prolly wana beef it up regardless, but a stock crossmember has no affect at all on doubler vs non doubler. The crossmeber would depend more on suspension design and potential doubler support. But really...where talkin like 50 bucks material.

As for driveshafts, the op is doing axle swaps. So redoing driveshafts is mandatory anyways. Even if the OP kept a stock 231, the pinion lengths change with his axle swap so shortening the shafts would be required regardless. (Well...probably.)



YOUR close....:flipoff2: :laughing:

Duff's is $525 shipped.

And yes, with enough intrest, I intend to be a new 231/300 vendor and will be about 100 cheaper. And my kit will be 100% CNC machined all 6061. Only the first 20 or so orders would be without the midshaft. Once I make enough to order shafts in bulk I will offer complete kits. Price is uncertain but Im hoping for 430 shipped.



Replacing a unibody frame just to say "FU" to other forums and people is stupid as piss.

T cases are easy. That is if you can effectivly use a wrench, snap ring pliers and in some cases...a press.



Actually, when i did my axle swap, i was able to use the same driveshafts as i had when i ran the dana 30/crys8.25 combo.as for the cross member comment, the reason i said he would need to beef up/ change the crossmember is because when you bolt up a dana 300 it adds weight to the back of the 231 housing which is aluminum and not supporting the wieght of the dana 300 can crack the aluminum housing of whats left of the 231.

The other thing about your logic is that your assuming this person cant set up gears so in turn priced the gear swap with installation prices... but he can build a crossmember, build all the adapter plates, build the shifters, etc... your not being consistent with is abilities...

From the standpoint of usability the doubler i agree would outway just regearing. from a cost and work standpoint i still believe its cheaper to regear specially if he went with a used set of gears.


In all actuallity assuming the guy can set up gears and build his own shit, they probly end up being around the same price.... either way its what he wants. the doubler would probly be a better option in the long run. I was just questioning his reason for wanting a doubler in my first post....