Upper A-Arm bolts

[galaxie428]

My rear tires have a bit of an inward camber to them so I thought I'd try removing some shims since I just put on some new tires. Is there a trick to getting that big bolt out? The nuts came off pretty easy but those bolts aren't budging. Any tricks you all have used? I'm about out of ideas, they pry bar isn't budging them either.

Speaking of shims, My M998 had one thick shim, one thin shim and then one that has 4 holes vs slots. I'm not sure if that is considered a shim or not? I don't carry any additional weight, any thoughts on what shims I'd need to remove to take out the camber to save me some trial and error?

 

[SmartDrug]

Tag for info. I’m in the same boat.

 

[AAVP7]

I recently removed a number of shims to correct the camber angle on my ambulance.

You probably can do this by removing the upper A-arm, but you can also do it with the upper A-arm in place.

Basically, you measure the current camber angle, and then go to a table in TM 9-2320-280-34 (paragraph 20-4). This shows you how many shims of which thickness to remove for which change in camber.

For removal, I loosened the eight bolts per side that hold the upper A-arm cups. Some of those bolts are a nightmare to get to, the wheel has to come off, but with a few tricks you can make it. The lower bolts are hidden by the A-arms, and you can´t stick a regular open wrench in there from above, as the body is in the way. I simply cut off a regular wrench to fit.

When all bolts are loose, spring tension will probably hold the shims in place, and you can´t push from above (body in the way again). I used a chain hoist to lift the lower A-arm up a bit, and that released the tension on the shims, so I could pull them out downwards.

 

[TNDRIVER]

My rear tires have a bit of an inward camber to them so I thought I'd try removing some shims since I just put on some new tires. Is there a trick to getting that big bolt out? The nuts came off pretty easy but those bolts aren't budging. Any tricks you all have used? I'm about out of ideas, they pry bar isn't budging them either.

Speaking of shims, My M998 had one thick shim, one thin shim and then one that has 4 holes vs slots. I'm not sure if that is considered a shim or not? I don't carry any additional weight, any thoughts on what shims I'd need to remove to take out the camber to save me some trial and error?

Place your jack "under" the lower a arm, loosen the bolts holding the a arm mounting bracket. Once they are "loosened" raise the lower a arm, this will unload the upper a arm and if you have the newer style shims they will slide out the top. If you have the holes only the bracket has to come off. I have mine completely removed and still have a slight positive camber. Easy way to check the camber is with a known good straight edge that reaches from rim edge to rim edge only, does not touch the tire, placed vertically and measured with a digital protractor. I got mine loose with out cutting up any wrenches but then again I have a bunch of different wrenches. After you get through with that these is the rear toe out to adjust! Just my 2 cents.

 

[galaxie428]

You probably can do this by removing the upper A-arm, but you can also do it with the upper A-arm in place.

I was trying to do it without removing the a-arm, the 4 bolts towards the front of the vehicle are easy to get to and I was able to get those loose pretty easy using an impact on the nuts on the inside of the frame. The rear 4 bolts are a lot harder to get to and even with the impact on the top two, I haven't been able to break them lose. The bottom two are going to be even harder with just a wrench. That is why I was resorting to removing the a-arm.

Place your jack "under" the lower a arm, loosen the bolts holding the a arm mounting bracket. Once they are "loosened" raise the lower a arm, this will unload the upper a arm and if you have the newer style shims they will slide out the top.

I tried that also but when I started jacking the lower arm up, it started raising the humvee off my stands. The TM doesn't say anything about needing to do this method so I thought I might be missing something.

I'm out of town this week so I'll have to give it another go this weekend.

 

[TNDRIVER]

I was trying to do it without removing the a-arm, the 4 bolts towards the front of the vehicle are easy to get to and I was able to get those loose pretty easy using an impact on the nuts on the inside of the frame. The rear 4 bolts are a lot harder to get to and even with the impact on the top two, I haven't been able to break them lose. The bottom two are going to be even harder with just a wrench. That is why I was resorting to removing the a-arm.


I tried that also but when I started jacking the lower arm up, it started raising the humvee off my stands. The TM doesn't say anything about needing to do this method so I thought I might be missing something.

I'm out of town this week so I'll have to give it another go this weekend.

4 wheels on the ground.