Grinding/Clunking Sound When Braking

[wraheem]

Hello All,

I've had a very interesting four months with my 2002 Mountaineer. About a year ago when making a sharp right turn I heard a very loud clunk sound. I did some searching and it sounded like it was a drive shaft issue. I put this off for a while and noticed that when parking that my wheels were "burning rubber" and I was jerking around turns.

About four months ago on the highway I heard a noise that sounded like I had a front right flat tire. I pulled over but no flat tire. A security guard told me it sounded like the hub was bad and I might lose the wheel.

I took it to Firestone to have it checked and told them I suspected it was a drive shaft problem. They said it was the right hub and didn't see a problem with the drive shaft. I let them do the work to repair the hub.

About three weeks ago I started hearing a similar grinding noises with some serious vibrations on the left side, so I took it back. They said it was a lose bolt in the differential that was causing the drive shaft to jump around. I had them remove it (drive shaft) but noticed a clanking sound that they said was due to bushings coming out of the differential (Keep that in mind).

I started noticing a low thump when braking at low speeds but couldn't see a problems with the brakes, rotors etc...

This weekend when staring out of a trip down south I noticed a grinding and metallic clunking sound when I stopped. I pulled over and raced around a parking lot trying to pinpoint the issue. I also noticed some clanking sounds when I drove away, but I assumed that the differential came lose again due to the jerking when I stopped. I went ahead on my trip thinking that maybe it was time to change the brakes again. I didn't here the noise again and thought that perhaps the problem "went away" (wishful thinking) but I was able to reproduce the issue. Whenever I travel over around 40MPH and need to come to a quick stop, the clanking grinding sound happens.

I took the wheel off after looking at the excellent sticky post about changing wheel bearings but couldn't find anything wrong; calipers tight, pad and rotor seems fine, and a barely noticeable play trying to move the lug nuts/wheel bearing up and down, and none left to right...

I'm at a loss at what's wrong, and I don't really want to take it back to Firestone, in between getting hubs and shafts worked on, I also had to get the alternator replaced.

Because the drive shaft is already gone on the driver side, I'm pretty sure I can change the wheel bearing assembly if that's the issue. I know I can change the brakes/rotor/caliber if that's the case...

Any help would be greatly appreciated!!!

Sorry for the novel but I needed to get all the pertinent info in here...

 

[The Rainmayker]

Interesting.

I would get a second opinion from an independent shop or Ford/Mercury dealer.

Sounds like a hub and/or bearing issue to me. It would be the first time I ever heard of a differential causing an occasional noise without something catastrophically wrong that would affect it all the time.

 

[ovalboy]

My brother has an '02 Mountaineer AWD. He has a similar metal grinding/clunking noise. Through lots of trial and error, we noarrowed it to the right front corner ... or so we thought. To this point, we have replaced the left front hub and the left front half shaft thinking that was the source of the noise. The hub was bad for sure, but the noise continues.

So we work our way around to the right side. Pull the right side (passenger side) half shaft thinking maybe that was it... nope. I stick my finger in the axle tube and all of the gear lube is sparkling with metal, and there are actually small chunks of metal laying in the end of the axle tube. The splines on the axle are fine. Now it's leading me to believe there is a more serious issue inside the differential.

I have not been able to find any information on front differential removal, rebuild, or anything of the sort. He has limited funds available and we are trying to do this as inexpensively as possible.

Has anyone had a similar issue? I've spent the last 2 weekends chasing this noise and working on the car and don't really feel like I'm any further along, and I don't want him throwing any more money at the car until we have some answers.

Your help is so greatly appreciated.