Thumping noise from right rear

[krammer]

I own a 1990 944 s2. It has apprx 120k miles. I noticed a thumping noise from the right rear wheel area. It starts about 25 mph and speeds up and slows down with speed of the car. Putting it in neutral and coasting makes no difference. Taking corners at lower speeds it goes away and then comes back when the car has evened out. If it were a bearing I would think it would be a constant sound at any speed. I would appreciate any help. Thks

[fiat22turbo]

CV Joint. You can swap them left to right so that inner joints end up as the outer joints to even the wear out, but if its already making noise you'll need to clean and repair the joints.

CV Joints - General Information, Removal, Installation, and Maintenance

[944tothefloor]

Yep, I agree. Clean and regrease the cv joints, and install them in reverse orientation. Use hi-temp, hi-pressure cv joint grease with moly. 100g per joint. Worked like a charm for me!

[krammer]

Thank you so much.... I always get good and quick replies..!

[9FF]

Once they start thumping you really need to change them, they are already worn. The repacking and swapping only works as a precautionary measure to extend the life.

Besides, swapping in new joints is the easy part, just removing the axles can be a pain. So having done the hard part you might as well put in new joints, then to prolong their life repack and rotate every time you do belt change.

[jeffrsmith]

When you replace axles, is it necessary to replace the bolts? I see a lot of posts where people replace the bolts, and I also see on eBay where a lot of vendors include new bolts.

[fiat22turbo]

Many people can't get the triple square bolts out properly since they don't want to buy the special bit for a few bolts and even if they do, they fail to clean the bolt heads out and gently tighten and then loosen the bolts, so they strip the heads more often than not.

Me? I replace the bolts with standard allen head bolts because I don't want to deal with the special fasteners in a roadside repair situation if I can avoid it.

[944tothefloor]

What's the real reason for the triple square on the cvs? Vandalism protection? Flipping the cvs is not as good as getting a new one, i know many people have done it because of a limited, expensive market. Then they got a ton more miles. Thumping is a pretty bad sign, but correctly regreasing, reassembling, and inverting the joints fixes it. i would only reuse a thumping cv if you caught it nice and early.

[jeffrsmith]

Originally Posted by 944tothefloor

What's the real reason for the triple square on the cvs? Vandalism protection?

I am not an engineer, but I believe it is to increase the surface area contact of the bolt head with the tool thereby allowing more torque to be applied while being less prone to stripping at torque specs.

[curtisr]

Originally Posted by jeffrsmith

I am not an engineer, but I believe it is to increase the surface area contact of the bolt head with the tool thereby allowing more torque to be applied while being less prone to stripping at torque specs.

Hence the name: Torx.

[fiat22turbo]

Originally Posted by curtisr

Hence the name: Torx.

Except they aren't Torx heads. They are Triple Square. If you use a Torx bit, you'll strip the heads.

[944tothefloor]

But they are torqued to 40 lbs, if I remember correctly, which a hex head can handle easily.

[9FF]

...Me? I replace the bolts with standard allen head bolts because I don't want to deal with the special fasteners in a roadside repair situation if I can avoid it.

I've never had a problem with those bolts. If I was looking for a practical solution there would be regular hex bolts in there all the way through with locknuts on the other end.

[968 GUY]

Check your lower shock mount bolt.