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2004 Suburban NR4 AWD transfer case / front diff problem


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Posted

Hello everybody! First time poster, long time reader, hate to have my first post be a question / problem, but thank you dearly for any help that can be had! 

 

I recently purchased a 2004 Suburban LT with the NR4 AWD option that had sat for a while and was missing its front driveshaft. I feel like I got a good deal, even if I need to replace a bunch of stuff, so here we go! I drove it home after getting it running without a front driveshaft, I was told that the previous owner had an issue of some sort and removed the front shaft in order to continue driving it, but he's no longer with us and everyone was unsure of what the issue was. I found a shaft used and installed it to check it out, upon my test drive I discovered that tight turns were nearly impossible, lurching and jerking and skidding the front tires like I was in a normal 4WD truck on pavement. Drained the front diff and it came out silver and chunky, and turning the wheels by hand felt terrible, grinding and rough and jerky. Had a mechanic friend look and we came to the conclusion that it needed a front diff, so I bought one! And it's only a bit better, sadly. I drained the replacement and it came out black, the drain plug had a little bit of shavings on it, but it feels good to spin by hand and the wear didn't seem excessive. Did I get another bum differential? How can I check out the Borg Warner 4482 two speed AWD transfer case? Would the differential in the transfer case cause issues like this if it had failed? I really like this truck, but would hate to throw 500 bucks or more at a used transfer case for it to be something I might be able to fix more easily, am I overlooking anything? Thank you for any help, this place has been a wealth of information thus far! 

Posted

The best and most accurate way to diagnose this over internet would be remove front driveline and see if it drives better. If so then t case is the only other component that can cause your symptom. Other than front CV axles which I would assume you checked out and felt them when front diff was removed and installed new one. I work at a transmission shop and see GM t cases blown quit often. 

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