Steel shims to go between your leaf springs and your spring perch. These are used on leaf spring vehicles in order to adjust pinion angles and achieve proper drive line geometry. Our shims are 2.5" wide, machined from steel, and include a new set of 3/8" diameter center bolts. Select size (in degrees).
Use the calculator below to determine the right size shims. The shim calculator figures out the current joint angle, takes into account how much the drive shaft slope changes as a result of the shim, and aims to achieve a 2-3 degree net joint angle. The calculator is only for double cardan rear drive shafts. If you have something else or if you have questions, give us a call. 801-737-0757
I spoke with a tech at Tom Woods and he explained not just what to do determine the shim angle that I needed but also why. The shims I purchased fixed my issue entirely.
Goood product. I had to cut and drill for my application but not a problem. Installed them and wandering of my old CJ5 improved.
I needed 10 degrees worth of shim on my '88 Blazer with an NP208. The shims worked and when I ran it back through the calculator it said I didn't need any more shim. The only reason for the four-star rating is because the kit is a little generic for what you pay. I had to grind the heads of the bolts down in order to get them to fit in the leaf perches on my axle. If it had been a perfect direct fit, five stars, but overall it's a great product and if you need shims this is about the only place where you can buy them made of steel at this steep of a degree.
Shims did the job perfectly thanks to the calculator. Would have been protracted trial and error to figure out all the variables on my own.
Just ordered the 5 degree shims on Tuesday and received them today on Thursday. I put a Dana 44 in my YJ a week prior and when the perches were welded, we did not have the Jeep nearby so we were unable to weld them to the exact degree needed. I installed with no shims and measured the pinion at 11 degrees and the driveshaft at 24 (SYE and double cardan). One degree of shim usually affects the difference between pinion & driveshaft by roughly 2 degrees varying by shaft length. I did some math and determined 5 degrees should be correct, and then I plugged the numbers into the handy calculator to make sure I was right, which I was. Installed today, and the 5 degrees of shim lessened the difference by 10 degrees on my 17" driveshaft setup, and I'm now sitting at 16 degrees at the axle and 19 on the driveshaft. Perfect!
Thanks Tom Wood for quick shipping, fair $40 price, and for offering a rare 5-degree shim option that nobody else seems to sell.