SRW and DRW describe the number of road wheels on the rear axle, not merely a trim or appearance package.
Physical identification
An SRW pickup has one road wheel at each end of the rear axle. A DRW pickup has paired rear wheels on each side and a wider rear body or fender treatment to cover them.
Why the distinction matters
Rear-wheel configuration can change payload, rear-axle and tire context, width, tire count and the model-year towing tables that apply. Do not transfer an SRW rating to a DRW truck—or the reverse.
Verify beyond appearance
Confirm the model, certification label, tire information and manufacturer documentation. Modified wheels or bodywork are a reason to investigate the configuration rather than guess.
General educational content for Canadian diesel-pickup research. Verify the exact truck, model year, certification labels, owner manual and manufacturer documentation, and obtain qualified mechanical or towing advice where appropriate.
Sources & Further Verification
Use the exact model year, VIN, truck labels and current manufacturer documentation when moving from general research to a purchase or towing decision.