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1997 Z71 Rear End noise

Discussion in 'Chevy Trucks' started by IndySnowPlowers, Dec 5, 2003.

  1. IndySnowPlowers

    IndySnowPlowers Member
    from Indiana
    Messages: 78

    have a 1997 1500 Z71. After 30mph I have a whirring or humming noise coming from the rear of the truck, definitely behind the drivers seat area. Below 30 mph and there is no noise.

    It only makes this noise when I am on the accelerator. I let off of the gas and it quits, hit accelerator again and it starts whirring. Changed rear diff fluid, no problems there. 4WD works fine and makes the noise in 4WD also.

    Tranny? Transfer case? Exhaust leak?

    I do have a small hole on the back side of my muffler at the very bottom. You can stick the tip of a ball point pen in it. Tranny shifts fine and truck runs fine. This noise is driving me nuts though.

    Thanks for any input.

    Steve
     
  2. Rick Loncosky

    Rick Loncosky Senior Member
    from 17557
    Messages: 102

    I don't know how many miles on your truck and or if you are the original owner, but it sounds like a pinion bearing is getting a little sloppy. Which means some disassembly :(
     
  3. IndySnowPlowers

    IndySnowPlowers Member
    from Indiana
    Messages: 78

    ok. I have 129,000 miles on it as of yesterday! and I am the second owner.

    Thanks for your input Rick
     
  4. Rick Loncosky

    Rick Loncosky Senior Member
    from 17557
    Messages: 102

    129,000 isn't a bad amount of miles to need some work. It just depends on how it was maintained. Maybe the gear lube has never been changed? Typical of a rear, if it ain't broke don't fix it, right. I know there are rears out there with twice that and still going, going and neglected. You can price the bearings separately at a local parts house or see if Jegs or Summit might have a kits a little cheaper. Good Luck!
     
  5. calhoun

    calhoun Senior Member
    Messages: 165

    I think the hole in the muffler is normal. I have it also, maybe for some kind of drainage.
     
  6. IndySnowPlowers

    IndySnowPlowers Member
    from Indiana
    Messages: 78

    I'll check on those kits.

    i never noticed that hole in my muffler before...I just started noticing water dripping out there. I could see why it would be there, just never have noticed it before!

    Thanks for the input guys. If I don't get it fixed before the first snow...I hope it holds up!
     
  7. IndySnowPlowers

    IndySnowPlowers Member
    from Indiana
    Messages: 78

    Rick

    well it appears you were right. Took it to get it looked at today....pinion bearing is the possible culprit. Of course they want to tell me i might need new ring & pinion and axle and everything else. Gonna take it apart soon and have a look see.