I have noticed on my truck (4K miles) that when i start the truck and back up for about 15 ft i get a snap, clunk, what have you. It's loud. My friend Doug Lindsey (D-MaxDoug-sorry about the spelliing Doug) asked me today about this noise, seems he has the same thing. I don't know what it is but am wondering who else has it.


thanks, mike

Dry transmission splines and slip yoke?

I had a grabbing, actually to the point of one of the rear wheels chirped as I turned and backed out of the drive. I drained the rear axle fluid, it came out grey in color, very thick, almost clumps.http://www.dieselplace.com/forum/smileys/Confused.gif I waited way too long to change it out, went to synthetic and mag-hytech, no noise, grabbing or chirping of tires since then.

Hey Mike I have the same thing, But for me its my wife Snapping her fingers at me and then when I ignore her she is throwing stuff at me when I back out of the Drive!http://www.dieselplace.com/forum/smileys/Big Smile.gif Other Than that Its the only time I hear Anything! Good Luck on this one. Kenny

Mine has never done it. Perhaps I don't back up far enough. I've found that lots of a my previous GM trucks have done it.

Mike,


mine did that--kinda of. I think there was a thread a while back about this.


Anyway--mine exhibited a delayed clunked--in other words--put in reverse--some delay and then clunk. Also--once--it did several clunks as I was backing up.


Mine did it around 5-6kmiles. I believe it is the rear differential. I had changed mine at 1500miles(diff half full) and then again after the clunking and it has gone away.


I use Mobil 1 gear oil--75w-90.


Hope this helps

Mike,


Mine did it for about the first three weeks I had it (1500 miles) and since then it has not done it at all. I now have 3800 miles on it. I haven't changed the rear fluids yet (lack of money) so I still have oem in there and it quit doing it. I figured it was just all the new parts having to wear into each otherhttp://www.dieselplace.com/forum/smileys/Confused.gif Try backing up for long distances to wear the reverse gears into their patterns. I do a lot of backing up, that's why I figured it was a gear pattern wear.


Dan

Mike, The rears seem to be a really strong point with our trucks. Maybe it's the parts holding the rear in place? Get an Air-hammer and tighten the spring U-bolts and hanger brackets.....couldn't hurt. http://www.dieselplace.com/forum/smileys/Approve.gif GM does a pretty good job making parts and a so-so job of hitting the correct TQ....go figure. http://www.dieselplace.com/forum/smileys/Ermm.gif


Burner----------> http://www.dieselplace.com/forum/smileys/Big Smile.gif

I have it too. Happens sporadically.

I've never had it happen in my GMC, but my 02 2500hd 6.0 does it. It has since new and after a few dealer trips nothing has been found. It is documented though.

I had the same problem with the last 2 GMC Sierra's I had. Grease the slip yoke and splines heavily. On my '02 the dealer replaced my slip yoke with an upgraded "nickel plated" one. No more noise. Being that you have a crew cab maybe look at your 2 piece drive shaft

I have an '03. Mine would do this as I backed out of the garage. The truck is parked in the garage at an angle so when I back out my wheels are turned full. It bugged me but I could never find anything wrong. As you stated, it was only in those first few feet of travel that something would pop.


I haven't heard the problem for quite some time. I have almost 11K miles now and this problem occured when the truck was new (first few ?K miles). After reading the comments above, there may be some truth to changing the fluid in the diffs as the problem went away with either the diff change or just the additional miles on the truck.