One problem related to differential unit has been reported for the 2015 GMC Sierra 1500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2015 GMC Sierra 1500 based on all problems reported for the 2015 Sierra 1500.
Significant clunking in rear end indicative of improper alignment or lash is rear differential. Excessive vibration at speeds over 65 mph when the driveline is under load. Vehicle has been to the GMC dealership where it was purchased three times with no resolution to date. Current mileage is 18,000.