GMC Sierra got new seat covers which were a perfect fit to hide dirty stock seats having a lot of mould before cleaning. It was worth the money though they weren't cheap. [Video contains no voice]
Products below: ShearComfort,
- Premium set: Front: 40/20/40 w/ Solid Folddown Arm (Built in Cupholders and Tray) and Adjustable Headrests
- Premium set: Rear: 60/40 Split Back and Bottom w/ Pullout Arm and Adjustable Headrests (Crew Cab) (New Body Style)
I'm not affiliated with the seller. Just one example provided for your reference in considering to make your seats look nicer.