Clunking sound when turning in 4WD

[JimMorrissey]

Yes, it really just started happening. It started towing a trailer on a dirt trail and has been happening since in 4 low and high. One should not hear banging and harsh clanking when turning in 4WD on the snow and ice.

 

[JimMorrissey]

Well I bought and installed the new CV driveaxles. Everything went great until I took it out for a roadtest.....The noise is still there! It's a harsh clanking now and again, with a sharp metalic ping once in awhile. I wonder if something is really wrong with the differential itself. I'm not excited.

For those who have not read the rest of this thread, the vehicle is on snow/ice, not dry pavement.

 

[WTA]

I had a feeling this was going to happen.

I can give you a couple other things to check from service bulletins I remember and things I have found.

If it has torsion bars then get some good spray penetrating oil and spray both ends of them good. Sometimes they get some corrosion on the ends and make a heck of a noise especially on turns.

Rear driveshaft slip yoke.
Yes it can definitly make a noise up front. It will radiate anywhere it wants to.

GM has a special grease part number 123456 something or other. Seriously, that's how the part number starts. I just forgot the whole thing. Get that grease, pull out the rear driveshaft and grease those splines real well with it then put it back in.

SOme other things I have found that cause this are loose frame brackets, axle mounts up front and generally loose anything up front. If you have a impact wrench then get on every bolt you see on the chassis and frame up front and I'll be willing to bet you will find a loose one.
Those torsion bars and the rear slip yoke are the most common causes though.
I was a front end and alignment specialist since I retired from the Navy for GM and Ford BTW. I also went to vibration analysis school for GM. I learned a lot about weird noises there. I haven't worked for either of them in about 4 years now since I'm self employed now but these new cars and trucks are built so tight that really all it takes is one bolt coming loose or a bit or rust on some part that is supposed to move.

 

[WTA]

I just looked back at the year model of your truck. Go lube the ends of those torsion bars real good. It's almost always the left one but do both just to be safe. I've had lots of those on the rack. People around here complain about it all the time. If that doesn't fix it then go get that grease and do the driveshaft.

 

[TCBoomer]

I wouldn't bother with the grease for the driveshaft yoke. That noise is only present when coming to a full stop or when taking off. Turning has nothing to do with it. The rear driveshaft yoke is sticking on the xfer case output shaft and the correct fix is to replace the yoke with a nickel plated one. In a pinch, chassis grease will also work but it doesn't last as long as the special grease. What also works is stick a superball in the yoke before you reinstall the driveshaft.

As for the clunking on turns, most likely the spider gears in the front axle are the cause. Does your truck have the auto 4x4 option? If so, leaving it in 'auto' for extended periods of time have shown that premature axle failure results. The spiders fail which usually lead to chipped/broken ring & pinion gears. Drain the front axle and see what the fluid is like...most likely you'll find fragmented pieces or the fluid will have a fine metallic appearance

 

[wushaw]

Jim, when you turn the wheel you are putting more stress on the ft. driveline components than you would normally just going straight fwd...ok.
Now the CV joints you changed was a shot in the dark without verifying they were damaged, it was worth a shot but didn't fix anything.

You need to check the ft. differential for worn or damaged bearings or gears and also the transfer case, you could have a stretched/worn chain causing it to jump the sprocket under tension.
I would pull the ft. diff cover first since it is the easiest to check first.

 

[TCBoomer]

I would pull the ft. diff cover first since it is the easiest to check first.

Unfortunately there isn't any cover to remove. The front diff assembly on his truck needs to be removed and then split apart in order to see the gear set.

 

[wushaw]

Unfortunately there isn't any cover to remove. The front diff assembly on his truck needs to be removed and then split apart in order to see the gear set.

Yup your right, I forgot all about the 4wd IFS being so maintence friendly