Adding a flatbed, service body or crane to a chassis changes more than how the truck looks. It changes weight, and weight drives many of the rules that apply to commercial trucks. This guide covers the basics fleets in Texas and Louisiana ask us about. It is general information, not legal advice, so confirm requirements for your operation with the FMCSA, TxDMV, Louisiana DPS or your insurer.
Know Your GVWR
Gross vehicle weight rating (GVWR) is set by the chassis manufacturer and printed on the door-jamb label. It is the maximum the truck can weigh loaded, including the body, fuel, driver, tools and cargo. Upfitting does not raise it. Federal rules generally start to matter for interstate commercial operations at 10,001 lb GVWR, and a CDL is generally required at 26,001 lb GVWR or more. Many popular chassis, such as Ford F-350 and F-450 or Ram 3500 and 4500, sit near these thresholds, so the choice of chassis matters.
Body Weight Eats Payload
Payload is GVWR minus the empty truck weight. A steel flatbed is lighter than a fully loaded service body with a compressor and drawers, and a crane adds still more. Walk through the numbers in our guide to calculating payload after an upfit before you order, so you do not end up over rating on the first job.
Single vs. Dual Rear Wheels
A dually (DRW) carries a higher rating and is steadier with heavy decks or cranes. Single rear wheel trucks are lighter and cheaper to run but have less margin. Match the axle and tire ratings to the body you plan to install.
Common Compliance Items
- USDOT number and markings: required for many commercial vehicles in interstate commerce, and some states apply similar rules to in-state work.
- Lighting and reflectors: working tail, brake, turn and marker lights. See our LED lighting upgrade guide.
- Cargo securement: proper tie-downs, working load limits and tie-down points. Our comparison of airline track vs. D-ring tie-downs helps with layout.
- Inspections and records: keep annual inspection and maintenance records. Our preventive maintenance checklist is a good starting log.
- Trailer towing: hitch, chains and brake controller must match the combined weight rating.
Plan Before You Buy
- Decide the heaviest load the truck will carry or tow.
- Pick a chassis GVWR with margin above that figure.
- Choose the lightest body that does the job. Aluminum can save hundreds of pounds.
- Ask your insurer and state agency which rules apply to your operation.
Talk to Star Truck Equipment in Wharton, TX
We help Texas and Louisiana fleets match bodies to chassis so the finished truck is useful and within its ratings. Call (979) 532-1486 to talk through your build.
