Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Rear-End Clunking !!

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Wully-Bully, May 29, 2002.

  1. Wully-Bully

    Wully-Bully Newbie

    Joined:
    May 29, 2002
    Posts:
    2
    Likes Received:
    0
    Location:
    Atlanta, Ga
    I've got another question that's just driving me nuts! I had the guys at 4wpw install the 4.56 gears. (Pretty satisfacotry experience with those guys too!)

    There was always this clunking sound coming from underneath when everything was hot. I thought this would go away when I had everything replaced on the rearend. With the exception of the axles and the carrier, everything is new. I saved the stock carrier because I thought it was a pretty good unit. I'm not sure what it is but I think it's the Eaton Posi or the Gov-Lok. Not sure what the difference is.
    Well, that turned out to be a mistake. It's still clunking when it gets hot. I put the limited slip lube in it and it still does it. Although it did seem to help. Has anyone had any similar experiences? Should I scrap this differential and redo the axle again? Or is this normal and I should just drive it until it blows up?
     
  2. dysphemism

    dysphemism 1/2 ton status

    Joined:
    Oct 26, 2001
    Posts:
    667
    Likes Received:
    0
    Location:
    Fremont, CA
    my moms bf had a rear-end clunk. It wasnt the diff but the u-bolts that were causing it. Maybe check that out.
     
  3. 91K5

    91K5 1/2 ton status

    Joined:
    Jul 5, 2000
    Posts:
    185
    Likes Received:
    0
    Location:
    Wichita, Kansas
    My stock 10 bolt rear started to make a clunk sound when the pinion bearing was worn out badly, but with your new gears they should have replaced it. Try looking around and shaking the driveshaft and see if maybe a u-joints gone bad or if something seems out of the ordinary.
     
  4. shane74

    shane74 1/2 ton status

    Joined:
    Feb 12, 2002
    Posts:
    4,100
    Likes Received:
    0
    Location:
    Vancouver, WA
    Have you recently lifted it? like just before/after installing the new gears? If so, the clunk could be your driveshaft. Mine had the same thing right after I lifted it. I took it to a couple of shops and they couldn't find anything wrong. Turned out that it was the new position of the driveshaft. With the lift, the driveshaft was extended and the splines were, for a lack of a better term, wearing in in a new spot. For a cheap fix, pull the top part of the driveshaft out and coat the splines with a teflon grease. Also, pump the top of the driveshaft full of the teflon grease. Believe it or not, it was my tranny guy that told me about it! I did that, and the thunk went bye-bye. FYI, the thunk was so bad I thought I had broke a spring or gears.
     

Share This Page