Off Roading Degree Shims

[Moab4x4]

I have NO experience with lifts at all. I just put a Skyjacker softride 4" lift front and 2" lift rear (2" blocks with 6" springs). It looks like the front skyjackers had an aluminum degree shim that got semimangled when the parts truck ate a Lumina. About 1/4 of the shim is missing on the narrow corner. Do I need the shims? What degree of shimming do you usually use for a 4" front lift?



Also, What about the rear bumpstops? They used to hit the 6" factory blocks. Do I need to lower the bump stop 6-8" now??



I used the 4" drop Pitman arm and adjustable drag link too.



TIA

Ken

 

[MickeyMiller]

Ken,

You need the shims. When you lifted the front you reduce the caster, the amount of 'backward tilt' that the top of the steering arm/relative to an imaginary line drawn perpindicular from the ground through the center of the front hub/axel. Caster is required to encourage the truck to track straight, the shims restore some of the caster lost with the lift.



Mickey

 

[Moab4x4]

Thx for the info. I will admit that it handles differently now. I didn't have any bumpsteer before but I sure do now that I have a lot more spring travel. Crossover steering here I come.

Ken

 

[wcjp]

Avoid aluminum shims at all costs. Two weeks of light pavement only driving on my Jeep deformed aluminum shims. Three years later the steel shims still looked great.