Rear Suspension Alignment

[ZR1North]

Some may remember that I was searching for a right rear wheel after striking a curb several weeks ago. Through magic of the Registry and Marc H, extremely fortunate to have found a new set of 93 wheels and now moved on to collatoral damage. Wondering if anyone has insights as to what damage these symptopms may be indicative of:

1) left side wheel-tire edge protrodue beyond the edge of the top of the fender (wheel well) by 1/2 inch, but the right side wheel-tire is recessed by 1/2 (like the rear end has shifted to the left by 1/2 (for anyone doing comparasions, I am running stock 11" sawblades and GY Eagle F1s - I seem to recall before the indicent, the tires were about flush with the top of the fender (?))

2) right rear (side that was hit) producing an "oscillating, whish" sound above 40MPH (doesn't sound like a scraping - definately not a grinding)

Just got car back from alignment. It tracks very well. Didn't notice the wheel difference (point #1) until I got home. Tech did an adjustment on the right rear to reduce positive camber (top of wheel was tipping out quite a bit after the hit) and said there is plenty of adjustment left.

Appreciate advice as always.

[Kevin]

sounds like something got shifted

[ZR1North]

Just looking at the rear suspension diagram (3D-12 of the Service Manual). Is it possible that the "Differential Carrier Bolt" got bent during the hit?

[ZZZZZR1]

Originally Posted by ZR1North

Just looking at the rear suspension diagram (3D-12 of the Service Manual). Is it possible that the "Differential Carrier Bolt" got bent during the hit?

What about the rear bearing?

Did you reuse the tire?

damage to the spindle?

Do you have a lift?


Still an issue the fuel level gauge?



David

[ZR1North]

Good questions, David. Tire seemed ok on a fast spin on the balancer and when balancing the wheel, so I discounted that. Bearing and spindle are possible suspects for sure, but having difficult time relating those to what appears to be the whole "shift to the left".

Yeh, still have the fuel guage issue. I disconnected the batt for 20 min, but the problem remains. I am resigned to taking a look at the pump/float assy, but need to get this suspension thing sorted out first. Going to put the car on the ramps later tonight to take a closer look. The hit is the gift that keeps on giving.

[WVZR-1]

The "rear axle shift" isn't necessarily something created by the impact. It's possible that it has been there since the car left BG. It's just been "brought to your attention" by the impact. There's many others out there with similar issues.

By all means check everything that you can check and pay "particular" attention to the front pinion area of the differential where the c-beam attaches. I've seen two cars that were "fractured" in this area, one for sure had "clipped a curb" the other had right rear damage and had "new parts tags" on some components. If it was a soft hit the fractures might not be readily visible, it will require a close inspection. I might have snap-shots of one, it's been several years.

The rear bearing replacement is almost a "just do it" if the impact was sufficient to do the damage you mention!

[ZR1North]

Thanks, guys. Just spent an hour under the car, and it's hard to beleive that the whole differential carrier could shift 1/2 inch with all the attachments to the frame (supports WVRZ's point I think). Furthermore, there isn't any evidence of shifting around the bushings where the carrier mounts to those areas.

New theory is that it is likely the bearing assembly as a couple of you eluded. Could have been compressed further on the axel shaft and twisted slightly on impact (contributing to the whine I am hearing?).

Anyone out there with Eagle F1s on 11" sawblades? If so, I'd be curious to know where the edge of the wheel/tires are relative to the fender (flush, protruding, or inside the fender well)?

[WVZR-1]

Originally Posted by ZR1North

Thanks, guys. Just spent an hour under the car, and it's hard to beleive that the whole differential carrier could shift 1/2 inch with all the attachments to the frame (supports WVRZ's point I think). Furthermore, there isn't any evidence of shifting around the bushings where the carrier mounts to those areas.

New theory is that it is likely the bearing assembly as a couple of you eluded. Could have been compressed further on the axel shaft and twisted slightly on impact (contributing to the whine I am hearing?).

Anyone out there with Eagle F1s on 11" sawblades? If so, I'd be curious to know where the edge of the wheel/tires are relative to the fender (flush, protruding, or inside the fender well)?

It shouldn't matter the wheel but the tire is likely important. You might want to drop a "plumb-bob" at the quarter edge, center of wheel and establish a dimension for others to check. Measure to the tire side wall. I can't help you. I use 50mm wheels with 16mm spacers.

Actually the tire might not be significant either. You're looking to establish the relationship of the differential to the body. You're only interested in the "difference" left to right.

[Shrek]

How does the rear camber look?
Positive camber on the left rear along with negative camber on the right rear will give you the same visual. I've had factory fasteners not hold their settings from running hard over track curbing and gators.

[batchman]

I would suggest getting under the car with some string.

Picking lowest accessible suspension points (depending on lift type), maybe front lower ball joints vs rear spring bolt, diagonal string length should be the same. If you don't have a lift that gives you a clear shot you could tie strings with washers to four points. Yep, I tend to do too much with too little...

Also have someone drive the car while you follow - is it crabbing?

Best of luck,
- Jeff