Wheel Bearing Going?
Discussion
Driving along a straight line... then swerve (safely) the car from left to right... if it's the wheel bearing, the drone will sound louder in one direction than the other. So if you swerve to the right and the drone is louder, then the NS bearing is shot. Vice versa for the OS bearing. It's common for the NSR bearing to fail first in a 911 that is tracked.
runner911 said:
What tyres are fitted to the car ?
The answer to your problem may be the tyres.Pirelli P Zero Assymetricos are notorious for making droning/rumble noises when partially worn.
Michelin Pilot Sports - could they do the same?The answer to your problem may be the tyres.Pirelli P Zero Assymetricos are notorious for making droning/rumble noises when partially worn.
I am pretty sure it's not gearbox or engine related, as I have knocked the car out of gear whilst going along the Mway & the noise is still there. I have also held the engine at about 3 - 3.5k revs when parked on the drive (for a few seconds) & it is not present then. Therefore, my thinking is that it must be the wheel bearing (but then I am about as mechanically minded as an amoeba!)
DanH said:
PolarExpress said:
Driving along a straight line... then swerve (safely) the car from left to right... if it's the wheel bearing, the drone will sound louder in one direction than the other.
Except when it doesn't like mine didn't 
If you want to test for a failing wheel bearing, then there is a much safer way that swerving about listening for noises. Jack the car up, grab the wheel at 12 o'clock and 6 o'clock and try to move it in its horizontal plane, then try again gripping at 9 o'clock and 3 o'clock for vertical movement. If there's movement in either direction you need a new wheel bearing. If you rotate it while it's off the ground you may also hear a grinding noise and rotation may be not be as free - it will stop more quickly due to friction.
Sorry but you can have a failing wheel bearing with no play in any direction because it usually only chips a minute piece out of the track and it can often only be heard under load.
Swerving can confirm the problem but not always.
Always replace both as the other will go soon anyway and it can be very difficult to find the right one.
If a bearing is really badly gone you can sometimes hear it on a ramp but it is not foolproof.
Baz
Swerving can confirm the problem but not always.
Always replace both as the other will go soon anyway and it can be very difficult to find the right one.
If a bearing is really badly gone you can sometimes hear it on a ramp but it is not foolproof.
Baz
Check your tyres first - I once had a porsche centre diagnose 2 new rear wheel bearings required at £500 per wheel. It turned out to need 2 new rear tyres, it was tyre noise from low tread.
That was 5 years ago on my 996 - 50,000 miles later, the original wheel bearings are still fine at 80,000 miles!
great OPC diagnosis! (for their margins!)
That was 5 years ago on my 996 - 50,000 miles later, the original wheel bearings are still fine at 80,000 miles!
great OPC diagnosis! (for their margins!)
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