Three problems related to differential unit have been reported for the 2002 Chevrolet Trailblazer. The most recently reported issues are listed below.
Front differential.
2002 Trailblazer was running bad around 34000 miles. Took it to dealership and they had to fix the rear differential and reprogram the 4 wheel drive transfer case. All repairs were under warranty. I am now having the same problems at 70000 miles. Dealership wants to charge about $2000 to fix the problems. Have talked to several other trail blazer owners and mechanics and it seems that gm has a lot of problems like this, but won't do anything about it.
While driving consumer found that there was a hole in the rear axle differential and as a result the vehicle could not be driven. This vehicle had one problem after another. However, on November 25, 2004 while consumer was driving heard a very loud noise. Took the vehicle to dealer, and was told that this time it was the transmission transfer case module.