Rear Diff Whining
 

[:@]I've got a bit of a problem with my truck. It's a 2000 z71silverado. I've replaced my rear diff twice now:( and yet it still whines when I drive it. It sounds like an airplane getting ready to take-off from the airport, when I drive it through a parking garage or through tight streets I always end up getting funny looks. However; when I take my foot offof the gas the noise seems to goaway that is until I accelorate again.After I replaced the gears it ran great for all of about 2 days then the whining came back just like before. If anyone has got any tips or useful advise I'd appreicate it.

Thanks.:)

RE: Rear Diff Whining
 

Welcome to the forum!!! Typically the whine is caused by loose fitting gears, when the play in the gears in passed the tolerances. Did you replace the gears yourself or did you take it to mech to haveit done?

RE: Rear Diff Whining
 

I had a mech do it for me. Infact he had it for over a month before he told me that he couldnt' fix it.[:@]I think that I spent over $1300 just for 2 days of peaceful driving. Do you think the mech used the wrong kind of spacers?

RE: Rear Diff Whining
 

Its possible, if you can take it to another mech (a good mech)and he should be able to pull the cover off and check the play without having to pull the gears. The last time I had gears replaced (in an old ford)I took the truck to the meahanic whoI hadput a rebuilt engine in it, and hesaid that they don't replace gears, it was easier to replace the whole axelwith an axel with the right gears.

RE: Rear Diff Whining
 

I had one that did that. Replaced the gears 3 times and it still whined. Finally replaced the case. Turned out the case was warped, and no set of gears was going to work right. Fortunately, it was under warranty.

RE: Rear Diff Whining
 

Good point.

RE: Rear Diff Whining
 

That is a good point, but that still puts me in a pickel because the area I live in is dominated by Japanese cars. Therefore 99.9999% of the mechs only know Japanese cars. I've even looked through the scrap yards and no one had an axle for sale. If the case is warped is there any hope of fixing or replacing it within reason?

RE: Rear Diff Whining
 

Where do you live? Did your mech explain why he could not fix it or did he just dump it on you?

RE: Rear Diff Whining
 

I live in Doha, Qatar. And no, the mech didn't explain why he couldn't fix it. I just got the "I don't know" look and a stupid grin, I can't tell you just how mad that made me.
I've been thinking about selling my truck, but I just love it so much. It really is a good truck to have here, but if I can't find parts or a mech to keep it up I'm going to have to sell it. That is why I'm here, to see if I can get any information that might be helpful.

Thanks.

RE: Rear Diff Whining
 

Is there any kind of dealership you can take it to that sells chevys?

RE: Rear Diff Whining
 

There is, but they are expensive. For example, when mytrans went out I checked to see how much the dealer would charge me for a new one and it turned out to be $5,479. If I bought it online and shipped it here it would have costed my some where in the neighbourhood of $1,000.See the difference. I was thinking of taking it to the dealer tomorrow and see what they have to say. Is there any other possible problems that might cause the whining?

RE: Rear Diff Whining
 

I think lose gears or warped housing are probably the only major reasons.

RE: Rear Diff Whining
 

That does look like the main cause of my noise. A couple of weeks ago I went to the dealer for spacers and I think that they told me that they didn't have 30-40 mm spacers. So the mech advised me to buy 20-30 spacers, do you think that is what caused the noise to come back?

RE: Rear Diff Whining
 

Probably.

RE: Rear Diff Whining
 

How could someone warp their diff? Could it be from rough driving? Perhaps from sand duning?

RE: Rear Diff Whining
 

I don't really know, maybe someone here can shed some light on this?

RE: Rear Diff Whining
 

Mine was in a 4-door sedan that was driven mildly. The dealership could not explain why it happened and blamed it on a factory defect... probably some sort of stress on the metal from the casting process that finally caused the warpage.

RE: Rear Diff Whining
 

What happened after the dealer found out that it was a factory defect? Did they replace it or give you some kind of discount?

RE: Rear Diff Whining
 

I had bought the car used from the dealer. It was covered by an extended warranty, so the replacement was paid for by that.