Hey guys,

About 2 years ago I replaced both fron wheel bearings. The right hand side was an original, the left was one from a PT Cruiser (needed one quickly). Result is, the fron left (PT) spins very freely. The front right is stiff. Neither bearing has any play in it BUT the stiff right side bearing seems to 'crunch' a little when turned without the brake disc. Kind of as if there was a flat spot someone.

When I drive my car, there is no wheel bearing sound. No 'whop whop whop whop' like I had before on both sides. When the car is cold, the brakes are perfectly fine. They don't stick or anything like that.

I can drive 200 km without touching the brakes and if I then touch them, a violent shake is felt throughout the interior. The steering wheel flaps from left to right. The same, just less noticeable, happens in daily driving (eg. to work and back).

At first, I thought my brake disc was warped so I measured it: about 0.02 mm which is well below a normal 'rule of thumb' of 0.5 mm. The pads were a little sticky but they aren't excessivly worn.

So now the only part that seems to be a problem is the bearing. Is it possible, that a wheel bearing can cause a violent ahake? Has anybody experienced this?

Cheers

Damien

 

Yes it can, when I first got my 14yrs ago, the PO had somehow had managed to break the race and it didn't show when I did the pry bar check. Like you, I heard a crunch sound, especially when turning left (it was the left bearing). Mine was intermittent because of the race going in and out of alignment and was a bear to track down. It disintegrated when it pressed out, ....those are some big bearings.

 

That sounds like mine. Though I did notice a little squeaks a few days ago when creeping past cars. So it wouldn't surprise me. I'll check both sides. Might as well, same effort ln both sides...

 

hell yes, and abs faults too

 

Yes it can..... did you check run out on both sides of the disc?


I would think that if the bearing was causing the vibration, it would do it even without braking, might depend on what's failed and how it failed I supposed.


Usually when steering wheel shakes while braking would indicate warped discs/rotors...


Since you say when rotating the wheels by hand, one appears to be tighter than the other, then you may have a faulty bearing.


Just for future reference - the run out spec allowed for 97/98 XJ 308 is .1mm as per Topix.

 

Run out was 0.02mm on both sides... Measured like this:



The 0.5 was as said a rule of thumb. Less ist of course better.

As described: when I pull away on a cold suspension, the brakes etc. All work perfectly. No flatter or vibration. The longer I drive, the worse the Vibration gets (no matter what rims/wheels are on the car). The brakes are now out of question, as they all work properly. I thought the hub was done but that too is fine and has no play. But that would affect the rotor/disc as well. I really want to see if I can test it when warm but I am not quick enough...

I'll order a new wheel bearing and fit it. Might be better... Might...

 

fingers crossed

 

Hi Damien,

You don't specify, but I assume you're talking about your '97 XJ8/X308?

I just cured symptoms like yours on a 2013 M-B E550 by having one of the front discs resurfaced and by cleaning the caliper guide pins and bushings and lightly greasing the pad ears where they slide on against the guide ridges on the caliper mounting bracket so the pads could relax properly.

The runout measured cold at the edge of the disc was 0.004 in. / 0.1 mm, significantly higher than you measured, but these discs are huge, much larger than those on an X308.

Based on your symptoms, I suspect you have a combination of a failing hub bearing, a slight disc warp that worsens as the disc heats up, and dirty/corroded caliper components that keep the pads in contact with the disc and heat it up as you drive.

Cheers,

Don

 

Hey Don,

yes, my XJ8. My biggest PITA in car form ever

I had the problem as soon as I fitted new discs as well as with the old ones. But I then also had badly worn wheel bearings... I cleaned up the entire brake system and adjusted the fitment of the pads (they were a little sticky around the edges where the contact the carrier bracket). The guid pins are corrosion free and weren't greased, as they won't seize in the rubber guides. The hub is clean and was thoroughly cleaned again. The inside of the disc was also cleaned off (any kind of rust and so on was removed).

As said, I'll gkve this side a new bearing and then check again. I'll jack it up again tomorrow or Saturday and see if the front right still turns freely.

 

Late response here--I don't know those parts well at all, but, to get a good answer, I think you'd want to hold the rotor firmly against the hub with the lug nuts lightly torqued. Pls. excuse if i have it wrong!!

 

Hi NEECAPR,

If you are describing a method of testing for play in a wheel bearing, that can definitely reveal any play in a failing bearing. An issue I have encountered frequently on X100/X308 and later front wheel bearings is that the bearings begin to fail and make noise long before they develop any discernible play. If grabbing the tire or rotor at 12:00 and 6:00 and alternately pushing and pulling doesn't reveal any visible movement at the edges of the wheel or rotor, the bearing may still be failing.

To confirm, I've often had to remove the wheel/tire, brake caliper and rotor and spin the hub by hand, feeling for any grittiness or undue resistance and listening with a stethoscope for any unusual noises. And even then, it hasn't always been easy to tell if a bearing was going bad. When this has been the case, I've removed the wheel/caliper/rotor from the other side so I could directly compare how both hub bearings feel and sound. This will usually reveal which bearing has more resistance, is less smooth and/or noisier. Of course, both bearings may be failing!

Cheers,

Don

 

Hi Don,
Thanks for review and info. I did a lousy job of explaining what I was thinking. First thought was-- looking at Daim's photo of the indicator setup--that we're looking purely for brake rotor runout presuming the bearings are good. I didn't even think about bearing condition--wishful thinking, eh!! I can see what you mean by checking for bearing noise and snagging as you turn the hub, everything else removed as you say. I'd suggest leaving the brake rotor--still snugged lightly by all five nuts--so you have solid rocking leverage for bearing checks.
Only goods news for failed bearing discovery is that you can postpone serious rotor checks until good bearings are in place!
I have a "fun' mystery on another vehicle which has a pulsating brake drag--tire speed, of course--start about 30 mph and down,. BUT, perplexing: about every tenth of fifteenth stop is absolutely smooth. Long story, lots of checks, rotor replacements anyway, three year old anomaly!!
Thanks again!!,
Cy

 

Here's something for you: brake disc/rotor was 'locked' to the hub. Turn it: nothing to be felt. Take the disc off, and you can feel the snag in the bearing. Otherwise absolutely no play in it. You can only feel if with everything off in my case shown above