Transfer Case/Rear End?

[TheBlizzard]

2004 Tahoe LS - 5.3l - Tow Package - 30k miles

I have researched problems similar to this and couldn't really find anything that led me in the right direction.

Here is the issue; 2WD if both wheels are spinning together there is no noise or problems that I can tell, however, if one wheel gets traction and hangs up it makes this god awful clunking noise. I can't tell if its from the transfer case or the rear end, it sounds more like it from the rear end.

I tried to have my dad stand outside while I spun out on some snow and he said he could hear the clunking but couldn't tell where from. And like I said it's only in 2WD and when one wheel is spinning while the other is hanging out it seems.

I am sure this has been discussed before, and as I stated I searched and searched but couldn't find anything that directly related to my problem.

Thanks in advance,

Blizz

 

[xav8r]

When my '01 acted up, I got almost no warning. Some noise like you're talking about and then the gears tore themselves apart. I was able to limp it to a shop and replaced the rear with an Eaton Posi-Traction. Good luck.

 

[str8wkd1]

it is probly the wonderfule rear that gm used it has some kind of wierd posi set up, My 03 does same thing Im just waiting for the day it flys apart. I was told it is normal it the design they used somthing like a flaper or somthing. Sorry this ramble probly wont help you but a little insite.

 

[TheBlizzard]

Actually that does help out a bit; I was more looking for people that have had similar problems and that may have diagnosed and got it fixed. Last night we got aroudn 4" of snow here in Minnesota and I was out this morning driving around and didn't notice anything; but that might be because both tires were spinning and it was slippery enough that one tire didn't lock up.

So the posi traction theory makes sense because what must be happening is that when one wheel gets hung up its trying to get the other one to get traction but it can't for some reason and something isn't quite right so its making a clunking noise.

What would be nice to know is if its something that we should just let destroy itself or can we fix something ahead of time to aleviate having to get a new rear end in the future.

Blizz

 

[Grebbler]

Yeah. Sounds like the G-80 GovLok rear end noise.

Mine did it shorty after I bought the truck and I about had a coronary. Oddly enough it seems to be working fine in the 8 inches of snow we just got and it hasn't make any more noises.

Mine happened when I got some wheel spin on a wet road turning a tight corner. I don't know if it was while locking or unlocking. But after I finished the turn it just went BANG! and I looked into the mirror expecting to see large chunks of driveline bouncing down the street behind me.

Just do a search here or any GM forum for G80 axle or Eaton Gov-Lok (sp?) and you will get more depressing news than you wanted. :hlp:

Greb

 

[BLACK_DENALI]

Check the fluid and make sure its full! Low fluid levels can amplify drivetrain noises.


How your G80 rear end works.

http://www.youtube.com/watch?v=KbMZ9vcYVSg

 

[TheBlizzard]

Check the fluid and make sure its full! Low fluid levels can amplify drivetrain noises.


How your G80 rear end works.

http://www.youtube.com/watch?v=KbMZ9vcYVSg

I like this demonstration.

http://www.youtube.com/watch?v=q-rQTHMVAuw&feature=related

 

[boostaholic]

Sounds like it's time for a detroit trutrac, gov locs (or grenade locs) are prone to failure on these trucks and they pretty much suck as a limited slip. Trutrac is a helical gear limited slip so there are no clutch packs to service like a standard lsd. I'm buying one as soon as my truck is fast, they're about $400 or so part # 913A481.