W210 E300TD front wheel bearing question

[dougjoy]

I recently started getting a judder from my brakes usually when applied at speeds in excess of 45 - 50.
I have replaced discs, pads and adjusted the front wheel bearings and am still getting it although less than it was.

I took off my offside front stub axle today to check the wheel bearings, I thought I was hearing a slight rumble when i turned it.

I need clarification. I found the inner bearing loose in the stub axle it moves out to the oil seal a distance of 10 mm and spins happily in the void. Should this be a press fit and solid in position or does it just find its own position on the stub axle.

Any info would help.

Thanks in advance

 

[wireman]

The bearings are taper roller bearings which as supplied are in two pieces, an outer ring which is pressed into the hub and an inner part which carries the rollers in a cage wrapped around the inner ring that fits onto the stub axle or shaft. These "inner" bearings will come out of the hole leaving just the outer ring in place if there is nothing to stop axial movement, the outer one behind the nut will drop right out (and onto the filthy floor) if you let it, the inner will be held in by the seal.
Bearings must be replaced in pairs and kept very clean during any work involving opening up their housings to the outside world, one tiny bit of grit will destroy them.
If you lift out the outside inner race it should be possible to inspect the running surface of the rollers and outer ring, these surfaces should be devoid of any marrs scratches or evidence of surface degradation i.e they should look like new.

 

[dougjoy]

Thanks wireman, I was careful in there and made sure nothing detrimental entered the bearings. So the set up of the inner floating is fine, I take it that it alligns itself on the shaft and secures with the outer bearing as tightened.

 

[astradave81]

did you sand the hub where the disc sits so it was all clean and shiney?? If not the disc will not sit perfectly flat and would still cause judder. Use a DTI to check for any disc run out. Be careful not to overtighten bearings you just nip them until the play has gone. Overtightening will burn a bearing out in no time at all.

 

[uprightbrian]

Brake judder

I have the same problem on my E300 TD. Have not had the time to fix it yet but it is the rear discs that are distorted. If you have not checked yours yet it might be a good idea to have a look.
Regards Brian.

 

[wireman]

There should be a little end float in the hub bearings (~0.02- 0.05mm) a dial guage is required to set this up.

 

[Xtractorfan]

All good advice also check your bushings and ball joints and even ur suspension struts.

 

[dougjoy]

Thanks to all for replies, I put new discs on the front and have checked all ball joints on front and replaced the ARB drop links both sides. I did replace the rear pads but not the discs.

I think I'll replace the rear discs this week and see how that goes, I've had the car for about 6 years and I cannot remember the rear discs being replaced before.

I will let you know if it clears the problem.

 

[dougjoy]

All Problems Cleared

I replaced the rear discs today and all the brake problems have gone. The discs were badly scored and the rear of the offside one had deep rust over half the brake surface. The new pads were trying to get rid of it but had not managed.

Apart from that there seemed nothing else wrong.

My pull to the left on the steering has also gone. Anyone any ideas why???

 

[wireman]

The pull was probably the slight binding that occurs on old scored disks being unequal on each front wheel.

 

[dougjoy]

Thanks to all for information received. I have just re examined the rear discs and it looks as if the inner caliper pistons on both the rear breaks were seized at some point causing the brakes only to be applied to one side. When I replaced the rear pads I must have freed them without realising But the rust on the inner faces was making the rear brakes ineffective and possibly causing the juddering that I was feeling in the brake pedal. The car must have passed it's last MOT with this problem and it's last Mercedes service with it missed.

All is well now so I hope this helps someone else who gets a problem like this.

Thanks again to all who replied.