97 S320 Whine Question
 

Anybody with a W140 S320 out there? I test drove a rather nice looking 97 S320 today that's got 107K miles and an asking price on it of $9,900:00. One thing worried me in particular. It seemed remarkably loud to me. Are these engines noticeably louder than the V8's? I've drive an S500 which I don't recall being nearly as loud. Also there was a very noticeable metallic whine that appeared to come from either someehere in the rear or the tranny. Couldn't be sure in the brief time I drove it. Could that be a diff or tranny problem?

- Peter.

I would suspect wheel bearings first, but it certainly could be anything.

Brett

I don't think the six should be louder than the V8. I noticed in the past that some engines just seem to be louder than others. I'm hesitant to buy a car that roars on take-off. It could be the rear end noise you're hearing but either way it seems like a problem worth checking out.

Are wheel bearings a common failure item on these? I'd have thought 107K would be far too soon for problems like that to start showing up?

- Peter.

I have a 99 S320 and have no such noise.. There is a blower under the hood that sorta sounds like a whine during the first couple of minutes after startup but otherwise as quiet a car as I have ever owned.

We had a '97 S320 in the family from new. I'd say it was a very quiet car, certainly no louder than the V8 models. A front wheel bearing failure was one of the few things that went wrong with it in the 8 years it was around.

They're nice cars, but if this one doesn't feel right, I'd recommend to keep looking.

- JimY

Transmission planetary failure was high in early model MB 722.6 transmissions, if the whine changes pitch when shifting thru gears, its transmission relayed.
A differential whine would be constant at any road speed.

I'd always think about the wheel bearing first in this case, unless you have a good reason to rule them out, especially since your other possible culprits are more expensive.

The comment about the noise changing with gear changes is a good one.

I had a 97 C280 with a metallic whine (roar) that sounded like it was from the rear at 60,000 miles. After replacing the wheel bearings, it was dead silent.

It's very difficult to diagnose noises over the internet. You're probably better off with a professional's opinion after a real test drive.

Brett

As someone mentioned, there is an initial whine that occurs at start up but only when the engine is cold. After it warms up (5 mins or so) it will go away.