My friend believes he bent one of his axles in the rear. What would be some of the symptoms?
We already ruled out some things such as U joints, unbalanced wheels, driveshaft.
What would be a definate "tell-tale" sign of a bent axle?
swap both rear wheels with two known good wheels. If the problem goes away, then swap the each of the old wheels back, one at time. If the problem resurfaces, its that wheel. If it still shows problems after swap the rear wheels, put it on a rack and take a detailed look at the axel tubes.
As solid as the case and tubes appear, it is possible to bend the tube and/or crack a weld. Then look at the link arms for bends. Last, its a unibody, according to how hard and what angle he hit it could be anything. have them do a 4-wheel alignment check.
I used to beileve 4 wheel alignment check was only needed on cars with independent rear suspension. I've since changed my mind.
Jack the car up and put it in drive with the enging running and stand back and look at the wheels. If you see a woble, remove tire and againg watch the axle as it turns. You will see it if it is bent. You dont need an alignment machine to find this.
I have this problem on my 80 LX. Up to about 40-45mph it's fine but the faster you go the more it starts to shake the entire car, like it's going to come apart. It's very easy to identify the side that is at fault. Mine happens to be the PS.
I jacked the rear up and ran it at idle in 1st, 2nd, 3rd and 4th with and without the tires on, but it really didn't look like it was wobbling too much. So I swapped the tires side-side and the problem stayed on that side so it wasn't a bent rim.