Curtis A. Franz

I took my car into the dealer today for what I thought was a wheel bearing problem. One can hear the wow wow sinusoidal noise between 45 and 50 mph. Otherwise, at lower and higher speeds it is a continuous growl. The car has 20K miles on it with an extended warantee. Thank goodness, because they called me back and said it was in the transmission.

Does this sound familiar to anyone else.

Jimbeaux

I had similar sounds on two ocassions with the beast. First was when it was new. Turned out that one of the rear hub bearings needed replacing. Most recently it happened again, but I was prepared to live with it, but when I had my front tires replaced due to notamal wear, the sound was gone.

Curtis A. Franz

The dealer called to say that the GM extended insurance rep had to come to the car and see for himself. He rode in it and the decision was to remove the third member, the rear axle, and disassemble it for a show and tell for him. The Service department manager told me that only two Chevy dealers in the states have the right tooling to disassemble it which is why it is usually just replaced. We shall see...meaning I am going to look over the disassembly too.

Curtis A. Franz

Okay I saw the differential broken down to its components and the bearing growl came from the pinion bearings not axle bearings. We are awaiting a Monday shipment of parts. Now this car was driven for about 21,000 miles over five years (Museum Delivery Sept 2005). I searched the internet and really don't find anyone with the same problem for a Corvette. Just lucky I guess.

Curtis A. Franz

Just searched the forum for differential gears and came up with a transmission gear whine string that apparently was a ring and pinion alignment problem. My problem was at lower speeds and more a lower frequency growl thana higher pitch whine.

Snagle

It is nice of you to document this for reference. Search will always be able to find your posts.

Keep us updated on the results of the fix.

2006c6keller

I have similar problems with my car and we have been eliminating various other rear end noises and we are down to the transmission and differential now. It goes in Monday to a more friendly dealer they use recommended by local speed shop that does GMPP work, they said that dealer could get a differential, etc. through GM much easier than they could. I talked to the dealer and they said the're waiting for me after talk and checking of history on the car. They said a rental car is waiting for me, I sure hope they are able to solve the problem.

Curtis A. Franz

Well the saga continues. I just got back from Chicago while the Az dealer had the car and replaced the four differential bearings and put in new seals. They said the noise was still there and I was notified that they are going for a whole new differential. I did see that the old pinion bearings did not move smoothly. I guess I have to say ...stay tuned. (18 Aug 10)

2006c6keller

Well, this dealer, Friendly Chevrolet, Dallas, Tx, kept their word and did the job right. They did everything that they promised. They put in the differential the following new parts:

1. Pinion gear,
2. Ring gear,
3. Bearings,
4, Seals,
5. Clutches,
6. Fluids,
7. Etc.

They even gave me "Preferred Owner" coupons worth $275, didn't know about or ask for. A surprise that I'm going to have to look more into.

In talking to the service director on my past problems (delay, delay, and delay repair - they reviewed the history) he said we don't treat people that way, and sure didn't treat me that way. This took three years and I went to several dealers, GM Customer Service who sang the "stealership" songs they were given.

It is sooo nice to get a dealer who wants to help. What a good feeling!

timd38

Glad it all worked out!

Curtis A. Franz

The order for a whole new differential got stretched out to 1.5 weeks now....It is due in on Aug 25th. It is approaching a month now since I took it in. I have to wonder if the noise is really the differential with those new bearings they put in my original diff. We shall see...I think.

Curtis A. Franz

The new differential finally arrived and was installed. The noise was still there but "changed" a bit. So the dealer borrowed the tires off of a new 2011 and my car finally lost its growl at 40-50 MPH. They worked over Goodyear and now want me to install new Goodyears for "half" price at $913 and I went for it. I have always been concerned that it was the tires and they were the ones that said differential. The new tires are not here yet. I have seen the repeated claims that Firestone runflats are quieter. My Goodyears at 20700 miles sure aren't. But wouldn't any new tire be quieter, thus I went for the Goodyears rather than Firestones for the price difference.

cthusker

Thanks for the info! I wonder if the entire problem was really tires to begin with?? Guess you'll never know for sure now... At least it's fixed and you have a new set of shoes for half price!!

vettedoogie

Hmmm, so they had your car all this time and did all this work and it boiled down to tires? Why didn't they try that first if there was any indication of that being the problem?

jimmie jam

Why? Because they don't make much money telling customers that it just might be the worn tires. This happens all the time.....

vettedoogie

True that...I hear ya.
BUT...I'm guessing that when GM figured out that they were going to have to cover it, they might have pushed to have that checked out first. Dealer must have pushed the issue in a different direction...

Curtis A. Franz

My hearing is quite bad and I had to leave it up to them. However, I was wondering if it was tires from the beginning.

Curtis A. Franz

In my opinion it was the tires now that I have heard it with the new differential and without the tires.

2006c6keller

If the dealers would only use one of their best tools to determine the problems of any thing that runs bearings, gears, etc. That is the 'CHASSIC EAR", this is a box with six microphones on clips with a microphone selection switch and headphones, you can pick the mike you want to listen to by changing switch position. Put the car on the rack and run it (the tires are off the ground) at any speed and listen to the different areas. Chevy dealers have these devices but don't seem to like to use them. I have personally seen one in action on my car. That was how they checked my wheel bearings and found a bad one. They could have determined the tire problem quickly, no noise on ALL of the other areas excluding the tires. Very simple! Some even use the stethoscope also.