Ive had this 2wd 2000 blazer since may. It has 141k miles on it now and so far i have been trying to fix any problems that i come across on it. The last thing that has been bugging me is a whine/groan from around 30mph- 60 mph. My uncle told me its the rear end making the noise. As long as i have the gas pushed it makes the noise but the second i let off the gas the noise quietens. here is a video of it.

http://www.youtube.com/watch?v=xSZjzs6XNwI

So far i have check the ujoints which seem fine, the wheel bearings in the front are tight 0 play, in the rear i am able to pull the wheel out between 1/16" and 1/8" but no up and down play if i try to move it 12 and 6 o'clock. I just changed the rear differential fluid and all of the gears looked ok, no gouges or chips in any of them and no leaks on the rear end. 0 play in the pinion as well. im running out of ideas. Any help is greatly appreciated. thx

 

When did the whine start? That's nearly identical (though not as loud) as my rear end after a shop butchered installation of my G80. They said the ring and pinion was of poor quality but I took my truck to a dealer afterwards and the mechanic said the wear pattern was way off.

 

It has whined like that ever since ive had the truck. Its more noticeable in real life than it is in that video because my cameras mic kind of sux. My uncle (mechanic) said that he thought someone could have did work to the rear end and didnt get the wear pattern back the way it was which could be causing the whine. How much did it cost to get yours fixed? Thanks

 

Hahahaha, you don't want to know.

Unless you know how to set up pinion depth and preload and backlash and.....

It's easier/cheaper to just buy a used rear end and install it, at least it was for me.

But then again I was trying to swap out an entire carrier. If your ring and pinion look ok, it might be worth it to just take it to a speed shop or shop that specializes in rears and pay them to set it up correctly.

Any shavings in the fluid when you changed? They would look like this:



I was able to buy a used rear with under 100K on it for $150. Bought new bearings, seals, gear oil, diff cover gasket and installed it. If you can get to a speed shop for less than what you would buy a used rear for in your area, do it.

 

no shavings just small specs. Thanks for the help, ill prolly check around on prices to have them fix it and see how much a used rear will cost. I dont have the money to either right now so it will be a bit before i can get it fixed.

 

I have the same problem, I replaced the bearings and seals, but did not know about spacers, still have noise. My question, since I did not put in spacers, will there be damage done to bearings, pinion, seal? I have been told that the pinion is to tight because of lack of spacers. If I remove the pinion and put in spacers would this get rid of howl or is pinion fudged?

 

Only way to know that is to open 'er up and have a look-see.