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Beer924 · Joined: 12 Jun 2025 Posts: 2 Location: Netherlands

I am afraid I posted this message in the wrong part of this forum, so I am posting it here again.
I recently replaced the differential bearings on my 1984 924 2.0. Everything was properly adjusted according to the specifications. After 1000 km, a humming noise occurs when I make a left turn. It doesn't matter at what speed, whether at walking pace or 80 km/h. This means there's pressure on the rear reacher wheel. I thought it was the rear wheel bearings. It's a similar sound. I replaced them, but the noise persists. Considering the vibration I also feel in the car, I don't believe the differential is incorrectly adjusted, which is otherwise completely silent in a straight line and in a right turn. It sounds like metal vibrating against metal, like an exhaust that's not properly positioned. But that's not the case either. Any ideas? Anyone recognize this? Could it be something in the suspension?

924RACR · Posted: Mon Jul 21, 2025 8:56 pm Post subject:

Wheel bearings or CVs would still be my expectation.

There are spacers for the rear wheel bearings, which can wear and need replacement... do you have play in the wheel, with the rear in the air? Perhaps play is allowing contact somewhere?
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Raize · Joined: 18 Sep 2013 Posts: 444 Location: Scotland

My anti roll bar rubs on my exhaust when it rotates during hard cornering (can tell from the witness marks) even though it's a good distance away normally.

Until I did my brake upgrade my front wheels also rubbed the inner arches when turning on full lock which also made a bad noise. This is only with 205 profile tyres so only 20mm wider than stock.

Beer924 · Joined: 12 Jun 2025 Posts: 2 Location: Netherlands

Just a quick preview. It started with a humming noise when turning left. It definitely came from the rear axle. I replaced the rear wheel bearings on both sides. No result. Now I have replaced the CV joints on both axles. One of the CV joints was almost stuck and could hardly tilt. Unfortunately, this didn't help either, except that the car also started to hum and vibrate loudly at 3000 rpm. Now it also does this when you drive off. I thought it might be the exhaust, but that is completely free. Now I hear a scraping noise in the middle of the car when idling. It gets better when I press the clutch. Now everything rattles, hums and vibrates while driving. Even at lower speeds. And if you release the clutch a little too quickly, you hear a thudding sound that you can also feel in the car. I'm going to replace the torque tube bearings.