ACDelco 20889025 Rear Axle Seal.
A common leak on the rear axle is the axle seal.
For 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018 GM 6.6L Duramax LML L5P
2500HD 3500 Silverado Sierra 6.6L V8 Duramax diesel:2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018
One seal required per side
A common leak on the rear axle is the axle seal. This can be identified by smoking and burning oil smell from rear brakes. It may be noticed by grease and buildup on the backing plates as well. If left alone, it can saturate the parking brake shoes and inhibit parking brake operation. If it leaks bad enough, it can get on rear pads and cause dangerously poor stopping performance.