2025 GMC Sierra 3500 HD SLT
The 2025 GMC Sierra 3500 HD SLT is a 401-hp 6.6-liter turbocharged with an allison 10l1000 10-speed automatic and four-wheel drive.
| Spec | Value |
|---|---|
| Engine | |
| Engine Type | 6.6L V-8 Gasoline (FlexFuel) / Duramax 6.6L V-8 Turbo-Diesel |
| Displacement | 6.6 L |
| Horsepower | 401 hp |
| Torque | 464 lb-ft |
| Valvetrain | OHV, 2 valves/cyl, VVT (gas) / OHV, 4 valves/cyl (diesel) |
| Bore and Stroke | 103.25 x 98 (gas) / 103 x 99 (diesel) |
| Compression Ratio | 10.8:1 (gas) / 16.0:1 (diesel) |
| Injection Type | Direct fuel injection (gas) / Common-rail direct injection (diesel) |
| Drivetrain | |
| Drive Type | 2WD or 4WD |
| Transmission | |
| Transmission | Allison 10L1000 10-speed automatic |
| 1st Gear | 4.54 |
| 2nd Gear | 2.87 |
| 3rd Gear | 2.06 |
| 4th Gear | 1.72 |
| 5th Gear | 1.48 |
| 6th Gear | 1.26 |
| 7th Gear | 1 |
| 8th Gear | 0.85 |
| 9th Gear | 0.69 |
| 10th Gear | 0.63 |
| Reverse | 4.54 |
| Final Drive | 3.73 |
| Fuel Economy | |
| Recommended Fuel | Regular gasoline or E85 FlexFuel / Ultra-Low Sulfur Diesel |
| Suspension | |
| Front Suspension | Short/long-arm independent front suspension with torsion bars |
| Rear Suspension | Semi-elliptic three-stage multi-leaf springs |
| Brakes | |
| Front Brake Disc | 14 x 1.6 in / 355 x 40 mm |
| Rear Brake Disc | 14.1 x 1.3 in / 360 x 34 mm (SRW) / 14 x 1.6 in / 355 x 40 mm (DRW) |
| Tires & Wheels | |
| Tires Front | LT275/70R18E – LT275/65R20E (SRW); LT235/80R17E – LT235/80R18E (DRW) |
| Tires Rear | LT275/70R18E – LT275/65R20E (SRW); LT235/80R17E – LT235/80R18E (DRW) |
| Dimensions & Weight | |
| Length | 250.75 in |
| Width | 81.85 in |
| Height | 80.87 in |
| Wheelbase | 158.94 in |
| Front Track | 68.1 in |
| Rear Track | 68.3 in |
| Ground Clearance | 11.18 in |
| Curb Weight | 7,151 lbs |
| Interior | |
| Headroom Front | 43.03 in |
| Headroom Rear | 40.12 in |
| Legroom Front | 44.53 in |
| Legroom Rear | 43.4 in |
| Shoulder Room Front | 66.02 in |
| Shoulder Room Rear | 65.3 in |
| Hip Room Front | 61.18 in |
| Hip Room Rear | 60.24 in |