4wd Shift Lever Rattle

sicsiksix · January 11, 2008

Well, I recently purchased a 2002 GMC 2500HD 4x4. It has 56,xxxkm on the clock and runs quite well. It has a few problems though which I am trying to resolve. First it has some piston slap on cold start up for about 5 minutes, which I know there is no cure for. Second it has what I believe to be some sort of valvetrain noise (thought it was accessory noise, but is still there with both belts off). Sounds almost like a rocker or lifter clatter on the passenger side. I'm going to check the oil pump this weekend for a bad o-ring as well as see what I can find in the oil pan (like needle bearings). The other problem I've noticed is that the 4wd floor shifter rattles quite badly until I put some pressure on it. Now I know others have fixed this with a stronger spring, but what I need to know is where exactly this spring goes and if there is an updated part from GM, or just a stock replacement. Will I need to pull the prop shaft and whatnot to get at it? or can I fix it from up top? Any input into this would be greatly appreciated.

EDIT: Sorry just realized this should have been in the Fullsize Heavy-Duty forum.

02silveradols · January 12, 2008

Well, I recently purchased a 2002 GMC 2500HD 4x4. It has 56,xxxkm on the clock and runs quite well. It has a few problems though which I am trying to resolve. First it has some piston slap on cold start up for about 5 minutes, which I know there is no cure for. Second it has what I believe to be some sort of valvetrain noise (thought it was accessory noise, but is still there with both belts off). Sounds almost like a rocker or lifter clatter on the passenger side. I'm going to check the oil pump this weekend for a bad o-ring as well as see what I can find in the oil pan (like needle bearings). The other problem I've noticed is that the 4wd floor shifter rattles quite badly until I put some pressure on it. Now I know others have fixed this with a stronger spring, but what I need to know is where exactly this spring goes and if there is an updated part from GM, or just a stock replacement. Will I need to pull the prop shaft and whatnot to get at it? or can I fix it from up top? Any input into this would be greatly appreciated.

EDIT: Sorry just realized this should have been in the Fullsize Heavy-Duty forum.

I have the same problem with the 4 wheel drive shifter and no one seems to be able to help me. I'm interested as well.

sicsiksix · January 12, 2008

Well I tried removing the pin at the base of the lever and replacing with a 5/16" bolt. Didn't stop the rattle, but did tighten up the lever a bit. Not sure why GM allowed so much slack. I'll take a close look underneath tomorrow and see what I can do. Gotta stop my door panel speaker grills from rattling tomorrow as well.

sicsiksix · January 13, 2008

Well I managed to fix my 4wd shift lever rattle. It wasn't actually the lever, rather the shift rod that connects the lever to the transfer case under the truck. There is a foam spacer between each connection on the rod. I just used a couple of anodized 3/8" washers to take up the slack. If it starts again I'll put a small spring in there instead.

02silveradols · January 14, 2008

Well I managed to fix my 4wd shift lever rattle. It wasn't actually the lever, rather the shift rod that connects the lever to the transfer case under the truck. There is a foam spacer between each connection on the rod. I just used a couple of anodized 3/8" washers to take up the slack. If it starts again I'll put a small spring in there instead.

Is it really hard to do or easy. Thanks

sicsiksix · January 14, 2008

On a scale of 1 to 10, where 10 is difficult. I'd say its a 0.5. All you need is a small flathead screwwdriver, and a few washers or something to space out the rod a bit. If I get a chance today I'll take a picture of what I did and post it up here.