Does the 2026 GMC Sierra 2500HD need premium gas?

No. Diesel.

$0extra a year

Miles a yearGas, $ a gallonPremium gap, $ a gallon

12,000 miles a year. Gas $3.20. Premium $0.60 more.

249 models (2026). One trim per model: the cheapest with a grade.

2026 GMC Sierra 2500HD: fuel grade by trim
Trim	Engine	Grade	Mpg	Regular, a year	Premium, a year
Pro Double Cab RWD	6.6L	Diesel	16 to 25	N/A	N/A
Pro Double Cab LB RWD	6.6L	Diesel	16 to 25	N/A	N/A
Pro Double Cab 4WD	6.6L	Diesel	15 to 24	N/A	N/A
Pro Double Cab LB 4WD	6.6L	Diesel	15 to 24	N/A	N/A
SLE Double Cab 4WD	6.6L	Diesel	15 to 24	N/A	N/A
SLE Double Cab LB 4WD	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 159" Denali	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 172" Denali	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 159" Denali Ultimate	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 172" Denali Ultimate	6.6L	Diesel	15 to 24	N/A	N/A
2WD Crew Cab 159" Pro	6.6L	Diesel	16 to 25	N/A	N/A
2WD Crew Cab 172" Pro	6.6L	Diesel	16 to 25	N/A	N/A
2WD Reg Cab 142" Pro	6.6L	Diesel	16 to 25	N/A	N/A
4WD Crew Cab 159" AT4	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 159" AT4X	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 159" Pro	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 159" SLE	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 159" SLT	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 172" AT4	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 172" Pro	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 172" SLE	6.6L	Diesel	15 to 24	N/A	N/A
4WD Crew Cab 172" SLT	6.6L	Diesel	15 to 24	N/A	N/A
4WD Reg Cab 142" Pro	6.6L	Diesel	15 to 24	N/A	N/A
4WD Reg Cab 142" SLE	6.6L	Diesel	15 to 24	N/A	N/A

Rivals

2026 GMC Sierra 2500HD and rivals: grade of the cheapest trim
Car	Cheapest trim	Grade
2026 GMC Sierra 2500HD	Pro Double Cab RWD	Diesel
2026 Ford F-150	XL 2WD Reg Cab 8' Box	Regular

Check the fuel door or manual before you fill.

Gas prices and the premium gap change by state.