Ordering the wrong size flatbed for your truck is a costly mistake. The most important measurement is your cab-to-axle (CA) distance — and getting it right ensures a proper fit. Here’s how to determine exactly what size flatbed you need.
What Is Cab-to-Axle (CA)?
Cab-to-axle is the distance from the back of your truck cab to the center of the rear axle. This measurement determines which flatbed configurations will fit your specific truck. Common CA measurements include:
- 38″ CA — Short bed SRW trucks
- 56″ CA — Standard SRW cab & chassis (most common SRW)
- 60″ CA — Standard DRW cab & chassis (most common DRW)
- 84″ CA — Extended cab-to-axle for longer beds
- 120″ CA — Commercial platform body applications
How to Measure Your CA
- Park your truck on flat ground
- Measure from the back of the cab (where the cab meets the bed) to the center of the rear axle
- Measure in inches — precision matters
- If your truck still has a factory bed, measure underneath it
SRW vs DRW: Which Beds Fit?
Single Rear Wheel (SRW) trucks use narrower beds — typically 7-foot wide. Dual Rear Wheel (DRW) trucks use wider beds — typically 8-foot or wider to cover both sets of rear tires.
It’s critical to order the correct SRW or DRW configuration. A DRW bed won’t fit an SRW truck, and vice versa.
Common Truck Fitments
- Ford F-250/F-350 SRW — Typically 56″ CA, 7-foot bed
- Ford F-350/F-450 DRW — Typically 60″ CA, 9-foot bed
- Ram 2500/3500 SRW — Typically 56″ CA, 7-foot bed
- Ram 3500/4500 DRW — Typically 60″ CA, 9-foot bed
- Chevy 2500/3500 SRW — Typically 56″ CA, 7-foot bed
- Chevy 3500/4500 DRW — Typically 60″ CA, 9-foot bed
Not Sure? We’ll Measure It for Free
Bring your truck to Star Truck Equipment and we’ll measure your CA and help you select the right flatbed — no charge, no pressure. Call (979) 532-1486.
