U Joint going bad?

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by BenEllis, Feb 11, 2010.

  1. BenEllis

    BenEllis New Member

    Hey guys,
    I just bought an 02 Z71 extended cab Silverado about a month ago. The truck is in great physical condition, engine is strong, no transmission slippage. The truck does have a lot of miles on it, 240k. I bought the truck to help out around the house and to have something to drive in the snow. I bought it from a dealership that checked all the major components out and said it was good to go.

    For about the last week to week and a half I've started to notice a slight jolt/clank or grab when I take off from a stop. It feels like there is some slack in the drive shaft or differential. It shifts through gears great, and the jolt doesn't occure when shifting. It mainly happens when still in first within the first couple of seconds from take off. I also notice it if I cost up to a stop sign, roll up and get back on the gas.

    From what I've read it sounds like it is my U-Joint? I didn't notice the problem when I test drove the truck or even when I got home. If the dealership greased the joint before I picked it up, could be a reason I didn't notice it till now? I will end up taking it to my mechanic to get it looked at, but I would obviously like to know, or have a good idea of what the problem is before I take it in.
  2. Mean_Green_95

    Mean_Green_95 Epic Member 5+ Years 1000 Posts

    Last edited: Feb 11, 2010
  3. Boltazar

    Boltazar New Member

    I was told by a mechanic that my u joints were bad, I gave it a look and the slipage was in the rear end. The pinion gear oil seal was shot, loss of oil and the rear had a lot of slap.

    If the emergency brake shoes are binding that could cause the rough start off after backing up.
  4. dshewy14

    dshewy14 Rockstar 100 Posts

    man it sounds like a ujoint. one way to tell is drive the truck for like 30 mins then get out and feel the ujoints. that should not be hot at all.
  5. Gambit

    Gambit Rockstar 100 Posts

    another easy way to tell if it is a u joint is to grab the yoke and try to shake your drive shaft. If it has play than you got a bad u joint. Dont just do it in the rear though also check by the t case.
  6. BenEllis

    BenEllis New Member

    Hey guys, I just got everything figured out.

    Took it in to my mechanic, it was the shackels ( shock assembly ). They are just getting worn and rusted, and as the truck squats on take off they pop loose, giving me the feeling as if someone is kicking the truck. He soaked them in WD-40 and said to keep doing that ever month. He said its not hurting anything driving it that way, just annoying. Said can replace them, 300-400$ job, but said wouldn't until the wd-40 stops working.
  7. travis_93

    travis_93 New Member

    i just got a 1999 z71 recently and it was doing the exact thing and i thought that it was a u joint. but here about 3 weeks ago my sunshell/gear broke in the trans and tht was 1200 to have fixed but when i got it back they was no more slack. so maybe u have a bad sunshell/gear whatever it is called. the bad sunshell is a common problem with these trucks with the 4l60e.

Share This Page

Newest Gallery Photos