Front wheel bearing issue - PeachParts Mercedes-Benz Forum

brandlj · #1 08-22-2012, 09:53 PM

Good evening all,
1986 300sdl. In Jan. 2011 at 122,000 miles I replaced front rotors, pads, sensors, brake hoses, and wheel bearings. It is now 20 months later and I am having a weird issue with my car. After a 10-15 mile ride on the interstate at 70mph, my right front wheel is getting hot. The rotor may have even warped a little. Mileage is now 127,000.
When you look at the right front wheel it is blacker with brake dust than the left, but the car does not pull to the right with braking. I flushed brake fluid Saturday, and it really was not bad at all. I flush every spring. The dust cap on the wheel has wheel bearing grease coming out of it. I pulled off the cap and the grease on the right front is very black while the left looks normal. I do not hear any strange noises spinning the rotor. I followed the FSM exactly when I replaced the wheel bearings. Why is my dust cap almost full of grease? It's like it is filling the cup.
Now when I replaced the wheel bearings, they were not made in Germany. They were made in Italy. Could I have a bad set of wheel bearings? I will probably go ahead and replace this side but what brand do I look for. I have seen Meyle and FEBI, but they are not made in Germany anymore. I think the Meyle were made in China. Is it dealer time? or the classic center so I can get real German bearings? Any other input from other people who have used different brands. What is Fast Lane selling? One of them says made in Germany, the other Japan? another Brazil?
I am hoping that I have not damaged my spindle.
Thanks in advance for the input

TheDon · #2 08-22-2012, 10:33 PM

What type of grease did you use? Was it rated for disc brakes?

Timken is one of the better brands.

t walgamuth · #3 08-22-2012, 11:05 PM

Could be brake dragging. Bearing could be too tight.

Turbo300Mercede · #4 08-22-2012, 11:05 PM

Sounds like to me the right front brake pads are dragging / not completely retracting causing the extra heat and brake dust. If the heat is excessive, the bearing grease would tend to go liquid and the heat might be causing pressure build within the wheel bearing cavity driving out the thinner grease.

May be time to rebuild the calipers or check to see if anything obvious is preventing the pads from retracting the same amount as the left side.

I would tend to think your heat problem is pad dragging due to your extra brake dust rather than bad bearings. Bad bearings make noise. You should probably pull them to check to see if their surfaces are pitted or discolored though due to the darker color of the grease.

Diesel911 · #5 08-23-2012, 01:05 AM

X3 on the Brakes as the first thing to look at.

Get the Wheel off of the ground and have someone step hard on the Brake and see if when you turn it the Wheel will turn freely.

Remove the 2 Caliper Retaing Bolts and hang the Caliper with wire from the Torsion Bar.
Grab the Wheel and see if you can feel any play in it.

I just finished up changing a Boot on my Lower Ball Joint today. While the Brake Caliper was still not mounted grabbed the Wheel to see if I could feel any paly; and, I could not feel any.
In the past I had adjusted the end Play with a Dial Indicator.
If I had felt any Play I either would have drug the Dial Indcator back out and re-set the Play or (if I felt a lot of play) pulled the Hub off and checked the Bearings.

If everthing was done correctly even a Made in China Bearing should last more than 5,000 miles assuming no abnromal abuse.

brandlj · #6 08-23-2012, 07:21 AM

Thanks for the replies. Calipers are rebuilt units on there for about 2 years. At that time I changed out the rubber brake hoses also. The bearing grease is being liquified and it is black and awful looking. Could be a sticky caliper, or a rubber brake hose, or I just had the wheel bearing too tight. Have had a lot of heat here, could be making it worse.
In the meantime, I will drive my son's truck till I can tear it down and diagnose. Wheel bearing grease was NOT the official MB brand that the FSM says we are supposed to use, but this is the same grease I use on my other vehicles and have not had any problems.
Oh the trials and tribulations of keeping a 26 year old Benz on the road!

daw_two · #7 08-23-2012, 07:28 AM

x4 on the brake --- definitely sounds like caliper is dragging.

PLEASE be sure to let us know what you find.

toomany MBZ · #8 08-23-2012, 08:55 AM

Any name brand wheel bearing grease should work, the other side is fine, right?

Much good advice here, if you decide on another bearing, the Meyle that has "Made in China" on the outside of the box, has on the bearings themselves, Germany.

The Timken I have has France on the bearing.

I gave away an outer set of SKF because they have Mexico on the bearing itself as the dust cap and more importantly, the inner seals don't fit.

I haven't heard back from the fella I gave 'em to.

brandlj · #9 08-23-2012, 10:37 AM

Monday is the day I look at this. I will post what I find. Thanks for all of the input.

Air&Road · #10 08-23-2012, 11:18 AM

My gut is telling me that you have a sticky seal or piston in the caliper.

Kestas · #11 08-23-2012, 11:37 AM

Assuming the bearing hasn't failed and spalled, dark grease indicates it was overheated and oxidized. This grease is ineffective and should be swapped out with new grease.

The seal may have suffered as well. When overheated, it'll get hard and brittle. You need to swap it out anyhow when cleaning and repacking the bearing hub.

brandlj · #12 08-27-2012, 06:53 PM

UPDATE:

I took apart the right front wheel bearing assembly today, Spindle looked fine, wheel bearings look fine, grease was black and awful. Rt front caliper looks fine, brake pads are wearing just fine, no difference between left and right side.
Cleaned it all up, new wheel bearing grease, put it back together and it drives fine.
Perhaps I did not tighten them correctly last time?

Still a mystery. I will report how this is doing as the weeks progress.

qwerty · #13 08-27-2012, 07:14 PM

Quote:

Originally Posted by brandlj

Perhaps I did not tighten them correctly last time?

Tight bearings might cook the grease but they won't cause excess brake dust. They also don't wait 20 months to cause trouble. Your symptoms point to a sticking caliper piston, which can occur on an intermittent basis. My bet is that you have not seen the last of the issue.

How did you set the bearing adjustment, anyway?

brandlj · #14 10-06-2012, 10:55 AM

UPDATE!!!!

The weather has been cooler here. Car has been running fine till Wed. of this week. After a 20 mile Interstate drive, I applied the brakes and the rt front caliper locked. It felt like the front end was going to fall off. Extremely violent left and right motion in the steering wheel. I came to a stop and the rt front brakes were HOT, HOT,HOT, and STINKIN'.

Skip to Friday, replaced the rt front caliper, pads still looked fine, cleaned everything up, found driver's side outer tie rod end bad, replaced that also.
I had to lightly have the rt front rotor re-surfaced, it was a little warped. Had it aligned also. Tracks straight and true.

Drives fine now!

All of the members who responded to my original post were correct, a sticking rt caliper. This forum is the best.

Now I have to figure out was is squeaking at idle under the hood. Water pump bearing? Belt tensioner, Belt tensioner pulley? Belt tensioner shock? Is my fan pulley loose? Oh well, the saga continues when you drive a 26 year old Classic.

Chad300tdt · #15 10-06-2012, 11:04 AM

Quote:

Originally Posted by brandlj

Now I have to figure out was is squeaking at idle under the hood. Water pump bearing? Belt tensioner, Belt tensioner pulley? Belt tensioner shock? Is my fan pulley loose? Oh well, the saga continues when you drive a 26 year old Classic.

Here's what I discovered with my SDL when I had your symptoms.

Before:
Coda, 1986 300SDL, the journey continues........

After:
Coda, 1986 300SDL, the journey continues........