Hi all,

I’ve been doing some suspension/brake work on my ‘79’s rear axle, and came across this unfortunate issue (video attached): both rear axle shafts seem to be bent out of shape and therefore wobble (which causes my drums to rub against the brake shoes in an irregular pattern).

I’ve been suspecting the car was in a “minor” accident, as there’s a small amount of body damage to the front bumper as well as the core support (my passenger side headlight sits crooked in proportion to the rest of the body, and on closer inspection it has been pushed in a little), leading me to believe maybe a previous owner slammed against something in front and then a curb which bent the axle shafts? (Mainly the passenger side, as that’s the worst one. Driver’s side wobbles less).

I currently have bearings, spacers, retaining collars, etc. to install, but had a few questions first:

1. Do you guys think I need a whole new rear end? (In case the axle housing itself is bent out of shape?)

2. Do my bearings just need to be replaced?

3. Should I swap in spare axle shafts from my parts car along with the new bearings (I’ve verified they’re straight; I might also swap the diff over as mine sounds clunky as you might be able to tell from the video).

What would you guys recommend I do?

Thanks so much for reading,
Pascal

 

if the old axle shafts are bent, then you'd want to replace them with the straight ones.
i'm not sure of a good way to measure the housing, but if you have a good rear axle, maybe its better to just swap that in?

 

If you are sure the current axles are bent, I would definitely replace them with known straight axles. Have you pulled the drums, etc off to check the run-out on the axle flange? Or does stuff just seem to be wobbling?

For checking axle housing "straightness" I have used 12"x12" (dimensions not so important) flat metal plates. They need to be thick enough to not flex. Mine are about 3/16" thick. Drill holes so that they can be bolted to the ends of the axle housing. I would drill the holes so that the plates are in the same "rotational configuration" You can then measure how well aligned the axle flanges are. That might not be such a good description, but hopefully enough to figure out ;-) Here is a picture of one of the plates I have used on my disc brake rear. It is a bit of work, but what isn't?

Carl

 

Re-reading I realize it is not exactly clear what to bolt the plates to. Bolt to the axle housing flanges not the actual axle flanges. Hopefully that makes more sense.

Carl

 

I modified a Toyota 8" rear axle and installed it in my turbo FB many years ago. I had to weld on new brackets, so I was concerned about axle housing warpage. If memory serves, the differential was already out of the vehicle, so I installed the bearings and put a tube all the way through the housing. This makes it easy to see if there's any issue by looking through the differential hole, or you can leave a bearing out and gun sight down the tube with a light.

 

Ah brilliant! I’ll definitely try that as well, thanks so much!

 

I have some axles from a 79-80. Came out of a low mileage axle.

 

Awesome, thanks for the offer! I’ll let you know if I need them; I have a parts car that’s in rough shape, so if those prove to be garbage then I’d love to take you up on the offer