I have a fab shop and do some vehicle design and repair work. We got a Cherokee in a couple of weeks ago and was asked to complete a link conversion started elsewhere. Using products already purchased we are trying to get this guy on the trail rolling on 36's.

The shocks I have to work with are a good length, 11" stroke emulsion shocks. I also have new coil springs that are for 8" lift. I am not sure where they came from but as the truck came in they sagged about 2". I began research and design a couple of weeks ago with little knowledge of this vehicle and came up with this side view.
http://farm3.static.flickr.com/2650/3680866219_a916956750_o.jpg

I had began construction uncommitted to any single design and using existing components chose a long arm parallel from the side to have a little more control over performance.
I first considered a triangulated upper link and began heading that way. I begin to uncover more issues with the truck, the joints were aluminum and some the damage from binding was more severe than we had originally known. I started to add steering design elements and saw the bump steer issue. I ordered a complete set of proper heims and now shifted to three link with a panard. Here is what I have so far. I moved the axle 4" forward from where it was when it came in and it looks like I need 3" (or may be 4) of additional bump stop. I am going to move the tie rod to the top, not committed to tie rod design yet. Would like to fix panard angle but I am hitting a budget concern. I have good panard to steering rod relation. any thoughts? I will remove the extra parts later. will it with with stock panard mount geometry and 8"+? without squirting the poly out of the shocks? the links are temp parts.

http://farm3.static.flickr.com/2533/3680883347_a2d076c4e7_b.jpg
http://farm4.static.flickr.com/3662/3680962931_1ef995b724_b.jpg
http://farm4.static.flickr.com/3655/3680963171_fd5393ef45_b.jpg
http://farm3.static.flickr.com/2445/3680963437_2f21edf6e4_b.jpg

on stock axles?


edit: how about some more pics of that old bike with the side car :)

Maybe I am not understanding something but, with moving the front axle 4 inchs forward you are going to run into binding with the steering. I think I only got about 2.5 or 3 inchs out of mine. I have high steer so my setup is a little different but you are going to want to mock everything up before you start burning everything in.

I see a few things:

1) Yes, those axles are going to :nuke: But it looks like a lot of work has already been put into them. They will be fine on the street.

2) The frame side mounts for the lowers kind of worry me. It doesn't look like the whole frame is plated, and I could see the unibody ripping. I would add some more plate.

3) You don't need 8" to clear 36s. It looks like the fenders are already cut. You will need 6.5" max.

4) The rear axle end LCA mounts are way too low. You could move them up a good 3"

Other than that, I like the three link with panhard idea. Don't worry too much about the panhard/drag link angle. Match them up the best you can. It sounds like you already have a good understanding of bump steer and how it works.

any more pics of the side hack rig? looks like a 2wd ural

</hyjack>

Whats the point of all this? I understand the want for performance but it makes absolutly no sense to spend all this time on stock axles. I think its great that you wanting to modify things the way you want them, but I also think you stupid for doing it the way you have. But whatever tickles you pink I guess....Normally Id say good luck here but for you........:flipoff2:

Whats the point of all this? I understand the want for performance but it makes absolutly no sense to spend all this time on stock axles. I think its great that you wanting to modify things the way you want them, but I also think you stupid for doing it the way you have. But whatever tickles you pink I guess....Normally Id say good luck here but for you........:flipoff2:

He said it's for a customer. He said it was already started elsewhere (axle may have already been trussed, etc.) He said there were budget issues, so axles may not be in the picture at this time. I think he is just looking for some advice to improve on what's been done so far.

i dont know if you guys missed it, but he said he got this in pretty much halfway done, and they are finishing previous work. i think hes just doing what they customer had started with and wants. hey, if the axles blow up, thats no fault of his.

well ya beat me

The decision to use the stock axles was made when the original constructor installed lockers (and no gearing). I was asked to use the existing parts Springs, shocks, axles, driveshafts etc. and get the truck out driving. The original suspension bracketry had been removed from the frame and the stamped bracket on the axle was buckled.

I moved the axle 4" from where it was located when it came through the door. I was supplied none of the stock suspension pieces. I suspect during the original modifications the axle had ended up going rearward as both the fenders were buckled on it's first outing. I had to put the rails back where they belonged first, the torn seams were repaired.

I told the customer the axles, brakes and gearing were useless. We are moving forward regardless with repairs.

The point of all this is a local stone mason brought in truck with tons of issues and a little $ to get something to drive after a hard day of hucking rocks. If I can make it work a little he will bring it back for more when the snow falls. I have thoughts about the most effective upgrades, including axles, gearing and chassis upgrades and have done tons of research.

In my shop now I have a cobra, a pro rally car, a '33 brough superior, two hill climb cars, the ural, a stunt bike, several turbochargers, three bridgeports, a CNC, 40 T punch press, 8' press brake, 52" power shear, assorted MIgs,. Tigs, torches, powder guns, mandrel benders, cage benders, lift table, fork lifts etc. and 10 pro mountain bikes,mX bikes, race gas, guns, dogs and fucking railroad tracks...:flipoff2:

thanks for the good advice, the ural is a enduro race bike with a machine gun.

Oh God, there's lockers in them.... :eek:

I see a few things:



4) The rear axle end LCA mounts are way too low. You could move them up a good 3"

Other than that, I like the three link with panhard idea. Don't worry too much about the panhard/drag link angle. Match them up the best you can. It sounds like you already have a good understanding of bump steer and how it works.

I have 11" between parallel CA's The angles and axle path are pretty nice. I am open to raising the lowers now (it's just tacked) Is the extra GC right next to the tire important considering that raising the LC's will add additional load to a nearly stock frame? I can go up 2" and use the upper mounts for the UCA's and get the geometry back.

I am going to lower the panard mount on the frame a couple of inches. I have some nice ford 1T van tie rod ends that are bigger all around with plenty of articulation.. gonna stick with ball joints for that annual inspection:shaking:

Oh God, there's lockers in them.... :eek:

ya, with stock ratios. It came in with an reversed pinion angle so it may already be fried. pity

thanks for the good advice, the ural is a enduro race bike with a machine gun.

Can you get some pics of that! As long as the XJ is in the back ground its still on topic :flipoff2:

The factory track bar mount wont cut it. Its a flimsy POS and the tierod wont have enough travel for the 6"+ of lift the truck will have. For an easy fix look up the Rubicon Express heavy duty track bar and bracket. I used this on my front suspension and overall it works well. After using this product for over 5 years now, the 3/8" bolt holes are starting to stretch. For a better solution build your own and tie it into as much as the "frame rail" as you can. Use something bigger than a 3/8" bolt as well.

AARON

I have 11" between parallel CA's The angles and axle path are pretty nice. I am open to raising the lowers now (it's just tacked) Is the extra GC right next to the tire important considering that raising the LC's will add additional load to a nearly stock frame? I can go up 2" and use the upper mounts for the UCA's and get the geometry back.

I am going to lower the panard mount on the frame a couple of inches. I have some nice ford 1T van tie rod ends that are bigger all around with plenty of articulation.. gonna stick with ball joints for that annual inspection:shaking:

I was thinking raisng the LCA mount for clearance, but it also looks like you have a lot of seperation at the axle. You are right, it is not as crucial being that they are closer to the tire, but it can still make a difference. Then again, I don't think this thing is going to see many rocks (and it won't last long if it does :flipoff2:)
The CAs really shouldn't be completely parallel. They should converge towards the frame side (about 70% vertical seperation at the frame compared to the axle) and as a general rule they should point towards the front bumper. Building some adjustability into the frame side upper mounts is nice. This way you can make adjustments easilty later if needed. I think my frame side upper mounts have four holes spaced about 1" apart. You can easily adjust anti-squat as needed. Have you ran the numbers through the four link calculator? It may give you a better idea of how the suspension will behave.

I have not done the calc thing yet, now would be a good time though. I lengthened and offset the track bar mount. It misses all the junk so far. I already decided to run a stress rod across to the other frame rail when I saw where it was going to end up. It will check to see if I can add more bolts or something, thanks for the heads up. The owner stopped by and mentioned more internals for the axles and we got things headed the right way in that department. There are tons of 'tons here in n'england so we should be able to find 60's and 14Bs aplenty and he knows everyone around here.

Here is the Ural in street trim, the owner is a soldier and I am storing it for him. He has been riding it to work in the winter, ya, vermont winter.
http://farm4.static.flickr.com/3627/3682175445_b524440e32_b.jpg

shot s of track mount mods

http://farm3.static.flickr.com/2511/3682175745_55b120c261_b.jpg
http://farm4.static.flickr.com/3599/3682989620_d8a195b517_b.jpg

Yeah, i think it's going to take more than that....

Holy shit.. he's paying you to bracket and build a Coil rear with the 8.25 rear! Wow, what a dummy.

Just slap it together, if he's dumb enought to waste all that money on linking stock axles,
he won't notice suspension geometry that's not perfect.

A few things to keep in mind:

-Make sure the coils are Jeep lift coils to achieve a proper ride...
you'll need at least 6.5" with 2" spacers over the coils to clear 36s.
Fender trimming will be necessary.

-With that Low Pinion Dana 30 front axle, you're gonna have to settle for a crappy pinion angle,
because you CANNOT rotate the pinion up too far, because it will set the CASTOR down into the negative
or hovering around the zero mark which is a recipe for death wobble 100%. Set the knuckles to 4 degrees castor
and adjust your front arms to keep it close. If it was a High Pinon front Dana 30, it would be much better... but
castor is WAY more important than pinion angle. Keep in mind when the suspenion flexes, especially when the drivers side
tire DROOPS down really far, watch that pinion angle to see what happens. THOSE ARMS ARE LONG!!!! DAMN! Most guys run 36!!
I'm running 41"! Those look like they're 54""""

-You will want to LIMIT the DROOP with limiting straps for sure, to keep the front
driveshaft/pinon angle in check... and to keep the shocks from over extending. You're gonna want to use a front shock that is around 32-33" EXTENDED.

-Make sure you're rear links are triangulated enough that you don't need REAR track bar.

-That track bar frame bracket needs to be MUCH BEEFIER.
They take tons of stress. Once you beef up the bottom mount, WELD it to the side of the frame..
you might wanna plate the side of the frame with 1/8" before you bolt it up. Then weld it solid.

-Honestly... I'd tell the poor guy to buy some Rubicon Dana 44 Axles or
even pick up some Dana 44s or a 44 front/ 9" Rear from a Full Size... and use better axles
for this build. It's SENSELESS for him to bracket and link two SHIT axles that WILL NEVER EVER HOLD 36s!

I searched for a "link" calculator and only found a roll-center calculator.

http://www.pirate4x4.com/forum/showthread.php?t=204893

http://www.pirate4x4.com/forum/showthread.php?t=168577
http://www.pirate4x4.com/forum/showthread.php?t=431136

This is local Getting it guys, all their rigs work well but have different driveing styles and designs.
http://www.azrockcrawler.com/_images/tech/2007/6-27-074link/4linksurvey.html

thanks for posting that ashman, reading you loud and clear.

First I have a question then on with todays progress. I understand the need for caster angle and how it effects the vehicle. The other side of that coin is joint angle. What is the limit of effective angle to the stock lower U-joint? I have 5 degrees to spare beyond the mechanical limit.

I took the advice about the weakness of the track bar mount. I fabricated a link from the new frame location across to the right-side frame rail. I think it will have a huge effect on the stiffness of the bracket and eliminate the flexing that causes the failures. I could be totally wrong though..


Here is a look at the welded off-set track bar bracket. I added something like six new pieces of flat stock on that thing


http://farm4.static.flickr.com/3636/3684935247_d1af63738e_b.jpg

the next thing was to make an anchor on the right side frame rail. I went to the location of the TB bracket on RHD vehicles. weird.

http://farm4.static.flickr.com/3663/3684934535_60e1f4ac1b_b.jpg

I then TIG'd up a section of 4130 for the frame link

http://farm3.static.flickr.com/2456/3685745724_78eb99113c_b.jpg


I then designed a drag link utilizing a poly on one end and a SRE on the other from 1-1/2X .095 4130. I was able to make it straight by offsetting the tube a bit. I ended up with a length of 33.75 working out. I drilled the D30 bracket for a 9/16 bolt (required for poly bush) I don't know if the nut will fit. What a shitty bracket design.

[IMG]http://farm3.static.flickr.com/2561/3685745436_315fb525d8_b.jpg

Track bar mount looks much better....

Track bar mount looks much better....


thanks, your rig looks sick!

I am up to trying to install a sway bar now. I got the stock one bolted to the frame. The link is supposed to go where the tie rod is. this part is ugly.

Updates? Is this thing rollin yet?

Please? :D :D :D :D :D :D