Evenin all
What are the symptoms of a bad rear wheel bearing and how do i correctly diagnose its bad?
Thanks

 

iownme, it is fairly easy. What you do is jack up one of the rear wheels so it is off of the ground. Then, place your hands at the 3 and 9 o'clock positions on the wheel. Using your hands, push/pull on the tire like you were going to turn it like it was a front wheel to make the car go in circles. Do you get any movement? If yes, then odds are your wheel bearing is bad. Just to confirm, get a second person to watch the suspension to make sure that the wheel is moving in relation to the suspension and not the suspension moving due to worn bushings and whatnot.

You can repeat the same checks at the 6 and 12 o'clock positions, but i would recommend using a prybar or the like. NEVER!!!!! put your fingers between the tread of the tire and the ground. If you can push on the side of the tire, that is fine. Having had a relative have a vehicle fall on his hand, lets just say it didn't end well. If you are getting the same sort of movement out of both of these checks, then this is confirming that you have a bad wheel bearing.

 

Thanks Thermo
Im getting a squeek from the rear in relation to wheel speed when i turn a corner, and now a new noise/feeling, it kind of feels like a growling coming from the other rear wheel..again in relation to wheel speed.
I just drove 2000 miles with the car pretty overloaded with tools ;@(
The tires were new before the trip and i do not see any uneven tire wear

 

Just jacked up and there was a good amount of play on p/s rear wheel. Ordered a new hub/bearing online for $75 inc shipping.
Same bearing was $160 at advance auto

 

iownme, the bearing sounds like it is the source of all your troubles. Replace it and see what you have left. This might be a good time to look at the reluctance ring and make sure that it is in good condition. Cost you a few more dollars at this point if it is questionable, but will save you a lot of time later when you have to troubleshoot it then.

 

Thanks thermo, what is the reluctance ring and how is it checked for condition?

 

When you pull the bearing, you are going to be taking off the large nut that holds the half shaft to the hub. When you pull the bearing off, you are going to see where the spline on the half shaft is going to go into a large "ball". Wrapped around this ball is going to be a metal band with rectangular holes punched in it. That is your reluctance ring. Make sure that it is fully intact and not super rusty. This ring sits pretty much inside the hub assembly on the back(inboard) side.

 

iownme: This is a broken reluctor ring on the rear axle (sorry of the lousy picture). Rust under the ring expands and snaps the ring at the weakest link between the holes. When it breaks, your ABS and traction control are hosed. The part is only ~$15, but the real 'cost' is getting to it, which is why Thermo correctly suggests inspecting it when you replace the wheel bearing.


Good luck.

 

This might help.

Put hand break on.
Jack car up and put it on axle stands.
Remove wheel.
Spray all nuts with plus gas and go have a coffee.
Using a 32mm socket and breaker bar, remove centre wheel nut.
Release hand break.
Using pipe pliers close the hand break and release the cable.
Remove the top break calliper (pad carrier) bolt.
Using a small prisebar, prise the pad carrier out of the way.
Remove the two bolts holding the brake calliper and move it out the way.
Remove the brake disk.
Using an extended 50torx undo the four bolts holding the bearing hub on.
Remove the bearing hub

Replace with new bearing hub and secure using the external e12 torx supplied with the hub.
Replace brake disk.
Replace brake calliper.
Replace pad carrier.
Using pipe pliers close the hand brake and locate the hand brake cable.
Put hand brake on.
Tighten the centre wheel nut.
Replace wheel and tighten wheel nuts.
Take off axle standsand take for a test drive.

 

Thanks guys, thats a great deal of info.
I have been having an intermittent abs/traction light issue for a while, that bearing or ring may be the culprit!
New hub should be here by tuesday.. Will update when i know more.

 

For removing the 4 T50 hub bolts, will i need a male or female socket?
Also... If i find the reluctor ring is bad, can i reassemble and use the car until i get a new one?.. And if i can do i leave the broken ring off or put it back on?
Thanks

 

The 50 torques is male.
The brakes will work fine without the reluctor ring. You just won't have abs.
Leave the ring off. Less lightly to cause damage.

 

iownme: If you inspect the reluctor ring before disassembling the hub, you can save yourself a lot of effort by replacing the bearing and reluctor ring (if needed) at the same time.

To inspect the reluctor ring, remove the speed sensor and look through the now open hole while slowly rotating the axle. Here's two pictures of intact and broken reluctor rings, from this post: Speedo not working, ABS and engine managment light on HELP

Intact reluctor ring: http://www.paharris.pwp.blueyonder.co.uk/nsr.jpg

Rusted & broken reluctor ring: http://www.paharris.pwp.blueyonder.co.uk/osr.jpg

The 4 bolts holding the hub to the carrier have a female Torx head - you'll need a male Torx socket to remove them, and to re-install them to 63 Nm / 46 ft lbs torque.

FYI, my Mercedes has many male headed Torx bolts, requiring female Torx sockets. But X-Type Torx bolts seem to have only female heads and require male Torx sockets. Perhaps a nuance of British vs. German engineers. Just an observation. No doubt, someone will point out a few male headed Torx bolts on our X-Types.

 

Thanks for all the great info.. I do believe the rear swaybar mounts have male torx head bolts ;@)
The swap did not go easy.
Hub was well seized to the axle shaft and required some pounding to get it off.
That caused an issue with the end of the driveshaft "bellying" out which then needed grinding down so the axle nut would fit on.
The (used) axle nut did not want to go back on so i foolishly tried the impact wrench, that messed up the first 3 threads on the driveshaft, so with tiny "V" files i filed the threads back into shape.
By this time the new nut had arrived ($30 for 2 day shipping)
With a little more grinding and filing the new nut went on just fine and the car is back on the road again... No more noise from rear end.
The reluctor ring looked in good shape.
Thanks for all the input, it was all very useful, especially the part # for the nut!!!