Driveline Clunk

Squirrely · February 4, 2010

I read a lot of threads about the driveline clunk. Most say to grease the slip yoke... I don't get it. The yoke on my rig is part of the seal that holds the fluid in the transfer case. So, it should already be lubed right?

I didn't get the clunk until I raised the truck 2" last week. Now there is a definite clunk feel in the driveline somewhere. U joint maybe?

Thoughts please.

kuhl_530 · February 4, 2010

I would have to say more than likely it's a U-joint. 9 times out of 10 that's where you're going to get your clunk (in my experience) plus lifts tend to be a little rough on u-joints, CV axles and chassis/steering parts.

Squirrely · February 4, 2010

I hope it's just the u-joint. I'm fairly certain they are origional and with 205K on them.

I've never done u-jounts, do they just press out? It looks fairly simple, but I've been wrong.

kuhl_530 · February 5, 2010

lol to tell you the truth I've never done them on my truck, either. I've done them on my old jimmy though. First you have to unbolt the straps that hold them into the yoke, then let that side of the drive shaft down. There should be clips that hold the other two caps on (the ones still in the drives shaft). Then you can pry them out with a screw driver or whatever else is handy because at this point you're replacing them, so what does it matter if you destroy them in the process. Installation is opposite of removal, just use a c-clamp to press the drive shaft caps into place far enough to place the clips in. If you buy greasable joints, you might notice grease coming out of them. THAT GREASE IS ONLY FOR ASSEMBLY! You still need to grease the joint prior to operation.

Again, this is just by memory from my jimmy many years ago, so if something doesn't jive I'm sorry. But for the most part they're all pretty similar.

Squirrely · February 5, 2010

I finally cracked and had to take the driveshaft in. The joints would not budge. It took some serious torch heat and a press to get the stockers out. $25 for labor... if I had known it was that cheap I would have just taken it in and saved myself the agony.

Zembonez · February 5, 2010

Is the clunk gone?

Squirrely · February 5, 2010

No it's not gone. It's far less of a clunk, but still there. Maybe the chain in the T-case is slacking???? I'm not too sure.

I hate to even write this, but there is some kind of a ticking sound coming though the floor shifter area. Similar to the tick the injectors on the TB make, but a lower tone. In gear, neutral, 4wd, 2wd, it always makes the ticking sound now. ughhh.....

Squirrely · February 5, 2010

So my clunk is caused by axle wrap.

It seems that the noise comes from the rear end. I put the truck in park and rocked it back and forth until the clunk appeared. The rear end seems to snap up and make the noise.

Is the rear end bad or should I shim to fix the pinion angle? 2.5 degree roll would probable help a lot.

Also, the clicking I hear inside the cab is the injectors. Odd.

exracer · February 21, 2010

So my clunk is caused by axle wrap.
It seems that the noise comes from the rear end. I put the truck in park and rocked it back and forth until the clunk appeared. The rear end seems to snap up and make the noise.

Is the rear end bad or should I shim to fix the pinion angle? 2.5 degree roll would probable help a lot.

Also, the clicking I hear inside the cab is the injectors. Odd.

raising the truck pulls the yoke out farther from the trans resulting in the clunk....very easy check....take a couple buddies to a vacant parking lot and have them get in the box and sit close to tailgate(added weigh forces yoke back into trans) do a few starts and stops and see if clunk is gone....let me know ...

Squirrely · February 24, 2010

So I loaded up the box. I can still get the thump. I'm fairly certain the rear is going... Been trying to fined a rebuld on craigslist. Or maybe a junker rear so i can swop to rebuilt the origional and still be able to drive.

kawtoy_77 · February 24, 2010

could just be a little wear on the ring and pinion gears too!

mcreyaufmiller · March 7, 2010

You should have gotten a pinion angle corrector bracket thingie with the lift kit. Any time you add a lift kit to a truck, the pinion angle has to be adjusted as well.

Squirrely · March 7, 2010

I shimmed it 3 degrees to correct the angle. The blocks came from a 2003 I used to own and I ordered the ubolts online.

The pumpkin is toast.... Multiple clunks and vibration during acceleration. Feels like I'm grinding the gears to powder. It got worse after I pulled a 1 ton ford out of the mud last week.

The good news. This guy I drug from the mud was so damn happy that he offered to find me a new axle. He was even cool enough to give me the "Not bad for a Chevy" compliment. Nice

So this will work out one of two ways right now.

1. I get a new or rebuilt 10 bolt or something similar and we both win.

2. He's full of it and I really hammered what I have for no good reason. Damn.