Reverse to Drive/Drive to Reverse Clunk ?!?!

[rockola1971]

True that except when one breaks under acceleration it's not like damage isn't done. Believe me I found out recently when a front one broke when I was testing my boost level lol. Almost took out the oil pan but the oil filter looked like it was thrown in a blender as well as a couple other parts. Fuses are meant to fail before damage happens, u- joints not so much. You need to replace them before they fail or damage will occur. And the faster you're going when one fails, the more the damage. I was only going about 30. I've seen what happens when one breaks at 80 and it can be pretty bad.

When I worked in a transmission shop id get to see some of the human screwups. On the 2wd rear ujoint fails it usually destroys the the tail section of the transmission which makes the whole transmission junk. On 4wd it will usually destroy the transfer case and even sometimes rip it off the transmission along with the tail section of the transmission ruining the cases of both. Thousands of dollars in damage not to mention the need for a new driveshaft and new ujoints that should have been replaced before it all happened anyway. The things we do to our trucks n hoes.

 

[bayviewnick]

The videos you watched were from YouTube not his truck, his was only an audio clip, no video so you cannot discern where it is emanating from. A guess is 'closest to the phone' but, a guess only. Beyond this, all being equal, I would start with the rear most joint and work forward.

 

[Jeri99]

I haven’t gotten underneath the truck yet...I definitely will this weekend...but when I recorded the clip I placed the phone right under the drivers seat...

 

[afpj]

Oh wow, our 02 Yukon 4x4 sounds same as Jeri's sound clip. I checked driveshaft for play last year and joints felt solid. I think it's been making that noise for over 100k miles (178k now) cause I really can't remember not making that noise. Granted, I don't go back and forth with drive/reverse too often. Back under car tomorrow to check again

 

[afpj]

Well, crawled under and pushed pulled and rotated shafts. The main rear shaft only clicks when I push up on it at the transfer case output. No visible movement. Nothing at rear diff. The front shaft to the front differential rotates a good 1/8inch back and forth, but I think it's always that way? No up/down movement though. I did not disconnect shafts... working on my back on garage floor just ain't comfortable.

Jerri99, what have you discovered?

 

[Jeri99]

I’m on my way to a buddies house...I don’t have anyone home to sit in the car shifting while I look underneath...I took a peek this morning trying to see if there was any play in the drive shaft...everything seemed pretty tight. I didnt try testing up and down movement though...I’ll continue poking around when I get there

It was the main shaft connecting the rear diff to the transfer case I was checking out this morning...I’ll see if my front shaft has that same movement afpj has

 

[Jeri99]

Sorry guys this weekend didn’t pan out as I wanted to with figuring out the source of the clunking...I was fighting against the clock yesterday as it got too dark out by the time I reached my friends place...and today it’s been like this all day....

 

[Jeri99]

Tried giving it a go today...weather didn’t hold up

 

[Jeri99]

Hey guys...got a chance to get under truck today and shot a little video...at the very beginning is footage of the u joint where the rear drive shaft enters into the transfer case...the second ujoint is where the front drive shaft enters into the transfer case...the clunking sounds like it’s coming from either one of these two ujoints...but maybe you guys might be able to see something or hear something better than than I can....

 

[drowssap]

I may be asking you to perform more steps than necessary but have all 4 wheels off of the ground. Truck does not have to be running....put into neutral and spin the shafts by hand and feel for where the play is located. Even though I saw some extra slippage by the pinion shaft in the rear.....it appears to be a problem externally. That could be good and bad. Depends on why it is slipping so much.