axel shim?

i did a bilstein5100/ OME 887 lift + AAL. Got the cyclic grinding which I know I can get ECGS bushing to take care of. But there is a Toyota TSB on the issue which I tried to have them take care of. Mechanic said angle of axle is off and I need a shim. I mentioned the problem goes away in 4WD and its in the diff. Because of the Covid, techs cannot go on rides with owners but that may be an option down the road. anyway, does anyone have info on shims to get pinion back in line? IDK anything about it or what I would need to do

 

is a diff drop kit the same as shimming?

 

A diff drop is not the same as an axle shim. An axle shim goes between the leaf pack and rear axle to correct pinion angles. A diff drop is a series of spacers that lowers your front diff to correct angles at the CVs. If there is a problem with the pinion angle you would have driveline vibrations as opposed to the grinding you described. A second thing to look at would be a carrier bearing drop which is essentially a spacer for the carrier in the middle of your driveshaft- that would also help pinion angles.

However, the symptom you described is more likely the needle bearing in the front diff which you are already aware of. If you’re not getting any driveline vibes other than that, I’d leave the rear axle alone until you replace the needle bearing with the ECGS bushing.

Focusing on one thing at a time will help you avoid “unnecessary” repairs.

 

thanks, could you elaborate on driveline vibrations? my vibration is definitely cyclic...just like i'm about to enter a toll and you drive over those rumble lines. Its subtle but i can feel it. Are driveline vibrations more persistent?

 

I second this.

 

Vehicle vibrations are extremely subjective. Some people are generally more sensitive to them than others but driveline vibes would feel sort of like you have a wheel out of balance (minus the steering wheel shimmy). The vibes would be relative to speed so they’d be more prominent at higher speeds and hardly noticeable at low speeds.

 

Can the mechanic drive the truck without you being in it? If you're talking about driveline vibrations, it may take some time to find the issue. Quite a lot goes into a driveshaft...

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