Three problems related to differential unit have been reported for the 2006 Chevrolet Trailblazer. The most recently reported issues are listed below.
The front drive axle that goes through the oil pan housing became off balanced, and the vibrations caused sequential breakdowns through all of the connecting parts during normal use, such as the oil pan axle seals, front differential seals, front differential internal gears, cv joints, wheel seals, and the corresponding front axle systems. When the wheel seal vibrated loose, the gear lube sprayed over the engine block, and caught on fire. The vehicle was towed to the shop. The mechanic predicts that the offending off-balanced axle may lock up while driving if not replaced. Note: the date listed is the date of the fire in the engine compartment, but there are many ongoing issues with all of the parts listed, especially the internal disintegration of the front differential.
Upon turning the four-wheel drive engaged unknown to me at the time because the selector switch did not indicate this. The truck became difficult if not impossible to turn at low speeds as this vehicle does not have a limited slip differential in the four wheel drive mode. While turning the tires on the outside of the turn make a larger radius than do the inner tires. Without any slip the vehicle tries to maintain the same linear footage travel by each tire. This causes the tires to bind lock up and skid during turns. I have researched this problem on internet forums and it seems to be a quite common occurrence and could cause crashes while turning. I have contacted the manufacture and the response was for me to take it to a dealer and pay for them to look at it. I declined their suggestion and offered the compromise of taking it to an independent mechanic at my own cost,to which they declined. Please note I did not ask them to repair the vehicle at their cost but only wanted them to examine the vehicle for defective design/material.
Noise from rear axle drive shaft clank at times when shifting 1st to 2nd autotransmisson and light traffic when stop and go under acceleration dealer replace rear axle gears only not the whole complete rear transaxle and then installed rubber spring mounts rear noise is worse now load whine in over drive from 42-to- 62 mph.