This is the third time I've gone to the dealership this time and finally they are agreeing with me that the noise I'm hearing is a rear-end whine. Now the only problem is they said if it was them they wouldn't worry about it. They'd just ignore it. So I've been from It's a tire noise, to its an exhaust drone (whatever the hell that is) to finally rear end noise. They did tell me they were going to call the MB dealer and see what they say about it, and they were going to check for a TSB on it.

 

I hate to say this, but welcome to my world of unresolved and it seems, unresolvable problems. I'm so sorry that you're going through this...

 

13...give us some specifics because I'm getting a "whirr" sound, at a very particular speed, in my XF. It's not the exhaust in my case, frankly, i'm not sure what it is.

I just noticed it last week, and I gave it a little test the other day to see if I could reproduce it...yep...everytime.

Here's the scenario. I'm accelerating and when I approach about 77 mph and I start hearing this whirring sound from the rear end. I lift off the accelerator (i'm slowing now) and it and it goes away. Accelerate and it starts again about the same speed. If I accelerate past about 83 mph it goes away, if I then lift off the throttle and decelerate back through the same mph range it's still there. I guess it's some sort of harmonics effect or something. It doesn't sound too awful or bad. Is this anything like what you're hearing/experiencing?

 

Just like it except when I have zero throttle and decelerate back through the same mph range it disappears. It bugs the hell out of me mainly because I drive 70 miles a day and it all interstate and I run 77-83 mph just to keep up with Nashville traffic. What makes it worse is my dad is the Chrysler Parts Manager of the dealership I go to. At the moment I working with a mechanic that not certified to work on the crossfire but at least he's willing to work on it.

I've been told by everyone "just turn your radio up." 1 that's not going to fix the problem. 2 I listen to talk radio so thats really not going to fix the problem. I've also been told "drive slower" Yeah thats going to work right up until I get rear ended, or some idiot shooting at me due to road rage.

 

I'll put my video camera in my car and see if I can record the sound...I've wanted to try an HDDP video setup anyway, this will be an interesting test.

 

The rear end noise you hear is not normal. It is an issue DC knows about. The fix is to remove and replace the complete rear end. Mine was replaced after one test drive to confirm I actually had the problem. The new rear end took about 10 days to be delivered to the dealer. The car was in the shop one day and everything has been okay since.

There is an old thread from about two years ago on the same topic. Here is the first and last post:

- With the windows up, stereo off, cruise control on... does anyone ever hear a steady noise at speeds of 60 mph and higher??? The noise I hear sounds like a low pitched humming sound that goes away if you change throttle position. Noisy fuel pump maybe??? Anything that can be done about it??? Thanks for any inputs.

- Update... The noise is coming from the rear differential and will only get worse as the car gets more miles on it. Took mine to the dealer yesterday. They pulled off the diff cover... way to much metal shavings etc in there. Corrective action: R&R the rear end. Parts should be here in a few days. Chrysler is well aware of this issue so anyone hearing the same noise, get it checked out.

 

Can you give me a link to that thread? Thanks I'm going to print this stuff off and send it with my Dad so he can show the guys at the shop. Maybe I can get this fixed.

 

I just talked to the dealer again and they are telling me its an exhaust drone and that MB is having the same problem. Something about the note coming out of the exhaust. I said funny I can't replicate this standing still with RPM's they said it's possible. I am so irritated. They told me Chrysler is aware and dealing with it and there might be a tsb within the next 3 months. I am so pissed off I'm just ready to sell it for what I owe.

 

Thanks BEN, I'll check to see if it's the same issue with mine.

 

Those of you who are having this problem what was the mileage on your car when you first noticed the sound?

 

I think that Dr. Z has something to do with this. I know at least one instance where he removed the rear end from a 300C, actually just the suspension, and left it in the person's yard.

http://www.jalopnik.com/cars/ad-watc...all-184642.php

 

Around 15,000. I'm now around 22k.

 

My started around 5,000 miles. Have 14,000 on it now. Drives me crazy!

 

I have it too. Definitely rear end backlash whine. Same speed and lift off gas and it is gone. Get really into the gas and it is gone. Just coast with small amount of gas to maintain speed and it is there.

My dealer wants to go for a ride to listen so that they can think of excuses of why they won't fix it I am sure. Not that I really want these monkeys taking apart my entire rear suspension system and trying to get it all back in there the same way. These are very complicated suspension systems. Do you really want these five thumb dealer messing with your ride?
I will live with it, until it falls out on the highway behind me. Then Dr Z will warrantee it. 7/70 baby. And I have a spare speedo head.