One problem related to differential unit has been reported for the 2005 Chevrolet Suburban. The most recently reported issues are listed below.
Began hearing a "whining" noise under the vehicle. Noise was progressively louder at accelerated speeds. Left vehicle at local Chevrolet dealer (CA) who did an inspection and diagnosed a mechanical issue possibly with the differential [ref. Claim check 175]. Service writer stated estimated repair cost for an overhaul was $3,000 vs. Higher costs to replace with used or new differential. Service writer further indicated continued driving could cause further damage and added cost if axle was also affected. Decided to take vehicle to a recognized powertrain repair facility who determined (also with a drive test) that the differential was the problem and gave initial $1,200 estimate. Authorized repair. Final cost was $813 and includes 1 year full warranty. Now runs smooth / quiet when driving. Technician indicated that although fluid level was good (sealed at factory), a ring inside the differential was bad (had become pitted and could have caused further issues if unchecked. Changed out ring and bearings but all other components including casing were fine. Technician stated such wear is uncommon for a vehicle with only 126k miles and with no towing on factory tow package. Is this an annomily or are there other cases of bad parts in differential for this make / model? would like to discuss further with gm zone rep. But no response!!!.