Measurements
Cargo dimensions.
| Length | Width | Height | Volume | |
|---|---|---|---|---|
| Seats up | 69" | 51" | 22" | 63 cu ft |
| Seats folded | 69" | 51" | 22" | 63 cu ft |
| Opening | – | 51" | 22" | – |
What fits
What fits in a GMC Sierra 1500?
Queen Mattress
Fits flat in any bed length with tailgate down
Full Sheet of Plywood
Lays flat in standard and long bed
Couch
Most couches fit upright or on their side
ATV
Fits in standard bed with ramps
Measure smart
What to measure.
Four numbers decide nearly every fit check. Get these right and the rest follows.
- 01The opening width and height of the trunk or liftgate, not just the total volume, since the opening is what an item has to pass through.
- 02The load-floor length behind the rear seats, then again with the seats folded.
- 03The height available under the roofline or parcel shelf, measured at the lowest point.
- 04Your item at its widest point, including feet, handles, and packaging.
Don't make these
Common mistakes.
Most “it didn't fit” stories trace back to one of these oversights.
- ⚠Trusting the cubic-foot figure and assuming a wide item will fit, when the opening is narrower than the item.
- ⚠Measuring the cargo floor but forgetting the roofline tapers toward the opening.
- ⚠Ignoring that a full-size spare, subwoofer, or hybrid battery eats into the quoted volume.
- ⚠Folding only one seat when the long item needs the full flat load floor.
Frequently asked
Questions we keep getting.
What are the Sierra bed sizes?
The GMC Sierra 1500 comes in three bed lengths: 5'8" (69"), 6'6" (79"), and 8' (98"). Width between wheel wells is 51" for all configurations — identical to the Silverado.
01Sierra vs. Silverado bed comparison?
Identical bed dimensions — the Sierra and Silverado 1500 share the same platform. The Sierra 1500 offers the CarbonPro composite bed as an option, which is lighter and more dent-resistant.
02
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