Rear Wheel Wobble (a lot of wobble!)

[Elaine D]

Another problem to solve......911 SC targa 1978.....we jacked up the rear of the car to remove the wheels to bleed the brakes after installing new stop light switches to master cylinder only to find the left rear wheel is wobbling quite a lot - just our luck. You don't notice this when driving along (no vibration or noise at all).

We removed the calliper and brake disc and found that the hub is wobbling with a lot of free play. The castellated nut is tight and there is no play in the drive stub shaft as such....it just appears to be the wheel hub itself (the bit the wheel studs are screwed into.) Not very knowledgeable in this area so apologies for terms used if not the correct ones!

We separated the hub from the stub shaft by removing the allen nuts and revealing the bearing (not sure if this was the right thing to do but bearing looks ok). This allowed us to move just the hub and it is definitely here that the problem resides, however can't get the hub out or away from the axle arm.

Our question is...Which bit is causing the problem? Is there a bearing that needs to be replaced in the axle arm, and is it a job for a pro with the right tools?

Thanks for any advice......Chris (Elaine's long suffering other half).

[Rory Mckenna]

Sometimes you could have mainshaft bearing in the transmission can fail and it'll sound and feel like the thing is bouncing all over the place... just an idea..

[VFR750]

Sounds like the rear axle bearing is shot. With a good bearing there should be ZERO play.

This is a duplex ball bearing, with a very strong press fit. Save yourself some real grief and have your shop do it. It'll cost about $450 to do.

If the bearing is really that loose, you will notice improved handling once it's replaced.

Unfortunately, you may want to step up to the plate and replace both sides. I say this because one side is really bad. That may be an indication of it use and exposure. Now your talking $900. That might be the price point where you decide to buy the tools and learn how to swear. My shop charged 3+ hours to do one side and claims its a PITA.

Ultimately, you have to decide how much you want to do yourself. IMHO, this was just too much learning for a once every 10 year thing.

[TRE Cup]

VFR is correct is his diagnosis; the bearing is shot AND you may need a hub. We have seen hubs friction "machine" themselves in the bearings when those failed. I don't see the need to do both sides at the same time. As a precaution , if funds are available, okay. But the bearings are really tough and last a very long time. There is no time overlap , other than a car going up and down on a lift, so no savings in doing both at one time.

The job itself is indeed a PITA ! Amatuers best leave it to a shop that has done them before- you don't want to damage more than you fix