6 degrees is an awful lot. Why do you need so much? Adding these shims will do two things, change your pinion angle and change your caster.

Chris

 

You could get the ones from BDS ( http://www.bds-suspension.com/shims.html ) and cut .25 inch off each side. You could probally run them without cutting them as well as long as they do not hit the front diff housing on the pass side spring.

--pm

 

especially in the front , you want to keep the punkin as level as possible. Shimming it aint a good idea. just my $.02 worth

 

DO IT.
i went to 8* caster, and steer with 1 finger now,
instead of 10 white knuckles.

 

Careful! You don't understand what his intent of adding shims is. If it's to adjust the caster for better on-road drivability, as in your case, then I agree. If it's to adjust pinion angle to resolve binding, then I disagree as on-road drivibility WILL be impacted (unless its a trailer queen). Regardless, he needs to understand the implications of adding shims.

 

They are difficult to find, my allignment shop found them for me. By all means, go for them. For all the negative posts, the reason you use shims is to correct the bad geometry we create when we all longer shackles, lifts, etc.

 

Shouldn't you be pointing the pinion at the transfer case? I've never heard of wanting to keep the pinion level. That seems odd to me.

 

The problem I am having is real twitchy steering and the steering does not self center. This is usually a direct result of too much negative camber. I already have a set of 3 degree shims and the pinion is level. I think I am fairly safe to increase to 6 degree wihtout any binding problems. The 6 degree should also help correct the steering problem. I believe that I am fully aware of the implications of adding the shims, but if there somehting I am not seeing please let me know. I appreciate everyone's answers. Please feel free to offer up any other opinions as I am very grateful for any and all help.

 

So, your pinion is level with a 3* shim(?). Your adding 3* more to correct Caster, which will point the pinion down 3* and will add to driveshaft binding when that side droops.

Are you using extended shackles or is it a scout axle or what? Why is the caster off to begin with? Get an angle finder and check the caster frist(6* to 8* is good), before you just start throwing different size shims in there.

If this is an axle your planing on running a long time, do it right, cut the perches and knuckles, set the correct caster and pinion angle and reweld it. In the end you'll be glad you did and it's not that hard to do(if you weld or have a friend that does), just a little time consuming.

As far as shims go, IMO, their a bandaid fix. It don't matter how long someone has used them on their rig, their still a bandaid fix.

 

Doogie...

Sounds to me like you understand the problem, and the resolution. Like one of the other fellows said, it is more of a bandaid, but will get you up and running. Adding more positive caster will improve on-road handling and will get your steering wheel to re-center. Too much caster and it will re-center violantly. Good luck finding the shims. Lots of places sell them for the rear, but I haven't seen them sold separately for the front. Might have to enlist in a local machine shop for those. Rancho *used* to supplier front and rear shims......but its been a while since I've seen one of those kits get installed.

Chris

 

How long of a shackle have you installed??

What I have done instead of a longer shackle is to add a spacer block between the frame and the shackle mount on BOTH ends of the spring and use standard shackles. Another way you could acheive the same thing is to fabricate new LONGER shackle mounts for BOTH spring ends. This does not change the pinion angle and caster . If you go for a big lift you may have to get a dropped pitman arm.
Thank about it.
I have been running the spacer (1")on all four springs, on mine for ten years with no problems.

DSD

 

I have thought about it, I really can't understand why you would go through all the work of cutting off all the spring hangers to add a spacer then reweld the hanger back on for 1" of lift. Plus the longer you make the hangers and shackles, the more stress your putting on the frame when lateral pressure is applied to the axle (in turns and off camber trails). I cracked boxed frames at the spring hangers and completely ripped the bolts out of the frame for the shackle hangers. In this post we are talking about a '72 with a unboxed, C-channel frame that is already weak at the rear hanger mounting point(comparatively to a boxed frame). Not try to offend you but IMO, this is a bad and unsafe idea.
Why not just buy the proper springs for the lift you want or make your own pack from leafs from used spring packs, it's OK to "mix and match"the correct size springs to achive what you need.

 

No offense taken. But this medthod places no more stress on the frame then longer shackles, less actually becuase you don't have to add two" to get a 1" lift. Yes I did box my frame, it was already cracked at both front and rear springs. As for it being that much work, that a personnal decision. As I said mine is a 73CJ, be running this modification for 10 years. Plus you don't create the pinion angle and caster problems. JMO

DSD

 

I run 5 degree shims, to restore caster and driveability after swapping out the stock D27 in my '71, for a '74 D30.
If you're going to use shims, be sure to use steel. Avoid any aluminum or other soft metals.
I had a machinist friend make mine to my specs. Since then, I found the link below.

Here's a link to reasonably priced, quality steel shims, available in custom sizes:

http://4crawler.cruiserpages.com/4x4/ForSale/Shims.shtml

HTH

 

I have a 73 CJ-5 with a 4 inch lift springs on it. They are brand new from Superlift. I have done a custom drag link with heim joints to get the drag link almost perfectly parallel to the ground. I have a slightly longer than stock shackle. It was advertised as stock length. My Jeep is really twitchy on the road and hard to handle at times. I have had the alignment done and was not told anything was out of specs. I am doing this as a quick fix for now and as an experiment to see what camber my Jeep works best at. After I get the perfect drive train in it I will have the front axle chopped and rewelded to correct for the camber and the pinion angle. Then I will be able to get some good strong drive shafts in there. I just put in a 360 in it and I have not taken it off-road yet due to an over heating problem. Now that I have that corrected I am dying to get this thing in the dirt. The problem is I have to drive it to the dirt. So now I have to fix the steering.

Doogie

 

In that you have stock lenght shackles disregard my previous post as it does not apply to your sisituation.

DSD

 

Doogie, do you have the print-out from the alignment? What did they report for your caster?
Spec is 5 to 7 degrees.
Mine was .9 (left side) and 1.1 (right side) after my axle swap. It was barely driveable at 35 mph. I added 5 degree steel shims, and it's completely stable now.

 

I do not have it any more. I have no idea where it went to. I had them fix anything that was out of spec and from what I can remember they did not mention the camber. I do know that the caster was out. I installed the spindles and brakes from a 78 dana 30 to get the big disk brakes. I am hoping that the new shims will make the Jeep a lot more stable.

 

Buy angle finder(less then 10 bucks) and it won't be a matter of hoping, you can check the angle and fix it.

 

I got the 6 degree shims in on Sat. I have been driving a little bit here and there since then. It appears that I have corrected my problems. The steering now self centers and it steers pretty straight. At least the best it will do for now. I am considering doing a shackle reverse to help with handling and the ride. My wife is complaining that it is a little rough when ever we hit bumps and it springs right back on us. I believe that the Jeep rides like that because of the shackle being in the front and as the spring compresses it pushes forward toward the bump and really makes it feel like it hits hard. I will post a new line on shackle reverse. Thanks to every one for their help and opinions.

 

I have a brand new set of 6 degree shims. I'll sell them to you for $10 plus shipping. They are too extreme for me. If you want them,e-mail me and we'll set up the deal.

 

Thank you but no thank you. I have already purchased a set and installed them. Thank you.