Rear Axle / Leaf Spring Wedge / Pinion Angle?

jkr wrote:are the springs you used the same ones that were on the van???
were they something from a salvage yard,or
are they something you bought and were told were correct.
the reason i ask is i can't see how flipping the rear shackels move the centerline that much forward and change the pinion angle that much.
the van MUST have had shims and they did not replace them.

My springs are EOM, they just reversed the shackles by mistake. Letting the shackles hang "down" raised the pinion angle by about 3" and that was too much, the rear U joint couldn't take it. Putting them back "up" got the pinion angle back where it needed to be, now the vibration is gone. My van had no shims in the rear, the shop just let the new guy finish the job and he goofed it putting ti back together.

The A100 shop manual is the ultimate reference here, no more than 6 degrees total variance across the drive shaft (from trans to rear yoke) is what Ive gotten from the local off road shop (who deals with lift kits all the time).

RodStRace wrote:

slowflapper wrote:

RodStRace wrote:Mine is that way too!
Gotta figure out what to do....

Get some axle shims from an offroad shop and get the angle back under six degrees

Yeah, I like the rake and figure if I flop the shackles it will drop at least 3 inches and I'll have tire clearance issues.
It does explain why it feels a bit tippy, it's gotta change the roll center big time, and this doesn't have a front sway (I did grab one from the JY). Another thing is that the tires are forward in the wheel wells now, not centered. Showflapper's is too, look at the photo of it on the tow truck.
I do still have the blocks from the 100 I pulled out. Guess the right thing to do would be to get new U-bolts, swap the shackles and add the blocks.

Mine was really unstable to drive with the rear that way, it felt really squirelly, both hands on the wheel type driving.

slowflapper wrote:Mine was really unstable to drive with the rear that way, it felt really squirelly, both hands on the wheel type driving.

This one was too when I bolted on the wheels (I didn't even drive it 100 feet with the old tires).
I put some 5 degree shims on the front axle to get some caster back and it's good now.
Will have to fix the rear though...

RodStRace wrote:

slowflapper wrote:Mine was really unstable to drive with the rear that way, it felt really squirelly, both hands on the wheel type driving.

This one was too when I bolted on the wheels (I didn't even drive it 100 feet with the old tires).
I put some 5 degree shims on the front axle to get some caster back and it's good now.
Will have to fix the rear though...

Exactly - I did the same when mine was wheel aligned - I run different tyre sizes front and rear, so it is the same effect as the rear shackles being reversed. Too much under-steer without the wedges under the front axle. Drives well now, and you don't need to hold the wheel while driving...much