2024 Gmc 3500hd Duramax Mpg. As we can see from these tables, the 2024 gmc sierra hd model with the highest towing capacity rating is the 3500 hd regular cab / long bed drw (dual rear wheel) with. Current truck is a 2014 duramax with the 6 speed.

Here’s the average duramax diesel mpg you can expect for popular trucks Find incentives, rebates, recalls, and.