changv

My C320 has an intermittent whine when driven moderately around 40 - 50 mph. It's not very loud and may be unnoticeable if the radio is on. It happens maybe 10 - 20% of the time. It can pop up all of sudden for a few minutes and disappear again. The noise level goes down when coasting. The build date is Dec. 2000 (serial # 629..).

It didn't make any noise the 3 times I've tried to have the dealer take a look at it. As such, nothing's been done so far. Does anyone have a similar problem and if it has been fixed, how?

TimmyC230boy

sounds like it could be a bad rear differential. Keep an eye on it. Don't be afraid to keep going back to dealer.

Yellow_Fly_Red

I have the exact SAME problem...

Yellow_Fly_Red

oops....
anyways....

I took it to dealership and had it checked out ...
and it turns out that me REAR Differential was the problem.

They are ordering a NEW rear differential for me. Should arrive in 2 weeks....

hope this helps.....

p.s. maybe you can drive the mechanic around and have him listen carefully for the whining noise....

I find that noise so annoying.. and embarassing when I drive my friends and they ask me about it...

hope you get it fixed soon....

changv

I did drive the mechanic around for about 10 miles, no noise the whole time (in fact, when I pointed out some other small rattles/squeaks, he said my car is better than most others he's come across). I'm pretty frustrated with this dealer. I've made an appointment with another dealer for this Friday.

They are also going to look into my radio's front/rear bias problem. They are a bit further away, and use Camry's as loaners. But, it's a small inconvenience if they can fix the problems.

o2bsurreal

Well, I finally took my car in for its "drivetrain whine." I told the guy there was whining coming from the back, and that I didn't have kids. Even after reading this thread, I wasn't convinced that my car would have the differential problem, but I wanted to be sure. Anyway, the service rep just called and said that the differential was in need of replacement and that he hoped to have it tomorrow.

The good news is that my loaner is a new Chevy Tahoe which I needed to pick up a new desk at Crate & Barrel.

Everything happens for a reason!

MarkL

Just as a reference, I haven't noticed any drivetrain whine on my 2002 C240 (6-spd), nor are there any rattles or squeaks. It's probably a good idea that you're going to try another dealer.

changv

I had my car in last week at a different dealer. Unfortunately, I had the same result. The noise was not evident when the technician drove it. I did not specifically ask them to check the differential; this was probably a mistake. When I go in again, I will make sure to ask them to check the differential.

Just curious, how did they check the differential? I hope it wasn't from a test drive as it looks like they will never my problem that way. The only other choice offered was to let them have the car for an extended period of time so that the technician can drive it everyday. I'm not ready for this yet; but, I'm getting close.

o2bsurreal

What I would like to know is how are our differentials wearing out permaturely. I realize it's a flaw somehow in the design, but I'm still really curious.

I'm not sure how they check a differential, but I'll try to remember to ask tomorrow.

mleskovar

There is a tech bulletin on installing a spacer to the mount between the differential and the body to eliminate a noise. Differentials don't have to be worn to whine, bad spec parts or faulty gear mating clearances can cause noise as well.