2005 Silverado 4x4 Z71 Odd Problem

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by rnichols, Apr 10, 2013.

  1. rnichols

    rnichols New Member

    In the last two months I have this problem happen twice. If i take a trip or go long distances with the truck, I come to a complete stop and go again, when I hit 10mph there is a loud 'clunk' from under the truck and it stops after that. It will keep doing it until I let the truck sit turned off for an hour or two. Then it disappeared and re appeared last night when I was driving on a trip. Same thing, let it sit for an hour or two and it stops. There was an error code thrown when this happened this last time, but I think it was un related, when they tried to pull the code at a dealership i found out there was an issue with my port, no power. Anyone know whats going on ? Truck has 114k miles on it.
  2. j cat

    j cat Epic Member 5+ Years 1000 Posts

    after you go for a long ride see if the U joints are all the same temp. if one is hot then that one is starting to go.
  3. buckmeister2

    buckmeister2 Rockstar 4 Years 100 Posts

    Could be u-joints, and they are cheap to replace, but i am thinking it is a tranny problem. Once power is applied to the driveshaft, the slack in a bad u-joint is taken up, and the u-joint would not suddenly make noise at 10mph unless there was deceleration, right? I suppose it could, but I have heard this same issue several times in tranny's that are aging, and when they really get up to the high end of the heat range, they may not fully downshift, they may develop a shudder on initial acceleration, the converter may only partially drop out of lockout (not sure about that one), etc.

    Next time it happens, pull up to a full stop and pull the tranny into low and leave it there while you accelerate away just like normal. See if it still makes the bumping noise/feel. If it does not, then I would suspect a trans issue. If it does, it could still be the trans, or something else. Just one of those things that you have to work at to eliminate all suspects (unless, of course, you go get your code read again to see if they were right about the port.
    Last edited: Apr 11, 2013

Share This Page

Newest Gallery Photos