2007 CTS Whine

rsilver39 · #1 (**permalink**) 04-17-09, 02:36 PM

I have a 2007 CTS with the 2.8L that has an annoying whine while dirving between 35 and 42 mph. The dealer has rebuilt the rear end, replaced the rear end, and replaced the transmission. Now they're telling me there's a Tech bulletin that basically says that this is a known problem, and if nothing shows any wear, and it hasn't gotten worse, it's a normal condition. The noise drives us crazy, as this is the speed range the one usually drives around town.

Wonder if others have had the same problem and might have had a solution. Got another two years on the lease, and it's driving us crazy.

3600cc · #2 (**permalink**) 04-17-09, 02:51 PM

Yup, my 2004 is like that and I believe MOST make some kind of whine.

Geez, if Cadillac provided some cheese with the wine it wouldn't be so bad...

Ha ha ha - I couldn't resist..

CTSV_510 · #3 (**permalink**) 04-17-09, 04:40 PM

First, do a search on the forum.

After you do, you'll find recommendations to get some high quality differential fluid like Amsoil Severe Gear Oil.

http://www.amsoil.com/a/synthetic-gear-oil

I use the 75W-90 in my diff that was new in August '08 and I have no whine yet and I do not baby the diff.

You may want to consider going to a higher weight like the 75W-110 or 75W-140 if your whine is that bad.

People have good results with this.

sterling · #4 (**permalink**) 04-17-09, 04:50 PM

When I got a fuel injector and throttle body cleaning that took care of most of the whine, which was previously very annoying, and I wasn't even expecting it.

z06bigbird · #5 (**permalink**) 04-18-09, 01:30 AM

You could take some 2" insulation and cut it to fit the trunk under the trunk mat. Cut another piece to fit under rear seat and under carpet in back seat of car.

Corvette and Camaro people make mods similar to this to keep the noise down. It works.

In the good old days, a good mechanic would diagnose the gear that was wearing (spider, planetary, ring gear) by the timing of the noise. Noise when you were accelerating was caused by one of these gears. Noise when you were decelerating was caused by a different gear.

Look for some gray haired mechanic or Ewill3rd on this forum, and he might be able to elaborate.

C66 Racing · #6 (**permalink**) 04-23-09, 12:16 AM

I've read on some other threads that going to a heavier diff fluid like the AMSOIL Severe Gear Extreme Pressure Synthetic 75w110 helps in many cases. Probably masking the symptons of a larger problem, but for a leased vehicle, probably not an issue for you.