How-to
How to Tell Which Cab You Have: Doors, Hinges, Window Sticker and Build Sheet
You need your maker's name for the cab, not just a door count, because that name is what running board listings use. Check the paperwork, run your VIN through NHTSA's decoder, then walk around the truck and look at the rear doors. It takes no tools and a few minutes. Four doors alone does not mean crew cab.
Straight answer
Look for the cab name on your window sticker or sales papers, then run the VIN through NHTSA's decoder. After that, check the truck: two doors is a regular cab, smaller or rear-hinged back doors point to the extended group, and four full-size front-hinged doors point to crew. Then find your maker's word for it, because listings use that word.
What you end up with: the exact cab name for your truck, the one a listing title will use. What you need: your truck, your VIN and maybe your old paperwork. No tools. A wrong answer here means boards that do not line up with your doors, so it is worth getting right before you spend a dime.
The steps
Check the paperwork
Look at the window sticker if you kept it, then the sales papers or a build sheet. Write down the exact words, plus the year and trim. We found no rule saying a cab name has to appear on a sticker, so if it is missing, move on.Run the VIN
Enter your VIN in NHTSA's decoder. NHTSA says the data is reported by the manufacturer. Read the Cab Type field if it shows one. Your VIN is on your registration or insurance card.Compare the doors
Stand at the side of the truck. Two doors, four doors of about the same size, or a smaller set of rear doors each point to a different group. See the table below.See how the rear doors hinge
Open a rear door. Note whether it hinges at the front edge, like a normal door, or at the rear edge. Note whether it opens only with the front door open. ARIES calls the smaller rearward kind "suicide doors".Find your maker's word
Match what you found to your maker's name for that cab. The truck cab types page has the full table by maker. Double Cab does not mean the same layout on every truck.Check it against the listing
Compare the cab name to the listing title, then run the fit check on the listing. If they do not match, ask before you order. How to check a listing fits has the rest.
What the doors tell you
This is the ARIES cab guide put to work at the curb. ARIES says plainly that its groupings are only there to aid understanding, and that your owner's manual is the thing to consult.
| What you see | Group, per ARIES | Other tells, per ARIES |
|---|---|---|
| Two full-size front-hinging doors, no space behind the row | Regular | Seats two or three |
| Two full-size doors plus a smaller set of rear doors, or none and seats that move forward | Extended | A smaller set of windows behind the first-row windows |
| Typically four full-size front-hinging doors, two full rows | Crew | Seats up to five or six |
Hinges help, but they are only one clue. ARIES describes crew cabs as typically front-hinging and the smaller extended-cab doors as rearward. Your own rear doors are the proof. Nissan's specs page, for one, lists the Frontier Crew Cab with a door count of 4 and rear doors as "Conventional".
Rear seat room is another tell. Ford's 2026 F-150 sheet lists 33.5 inches of rear legroom on the SuperCab and 43.6 on the SuperCrew, so you can feel the gap from the back seat. The Ford split has its own page: SuperCab vs SuperCrew.
Reading what NHTSA's decoder gives you
NHTSA sorts pickups into four cab types by doors and seat rows, so here is how to read them:
| NHTSA's label | NHTSA's definition |
|---|---|
| Regular | 2 door, 1 row of seats |
| Extra/Super/Quad/Double/King/Extended | 2 doors, 2 rows of seats |
| Crew/Super Crew/Crew Max | 4 doors, 2 rows of seats |
| Mega | 4 doors, 2 rows of seats, with a bigger cabin than a crew cab |
Two catches. First, the labels are groups, so it will not hand you the word a listing uses. Second, that second row says "2 doors" while lumping in cabs that have smaller rear doors, so do not use it to count your doors. Its "Double" sits in the extended group, while ARIES puts the Tacoma Double Cab under crew. If the decoder and your truck seem to disagree, trust the truck, then ask a dealer.
Mistakes that buy the wrong boards
- Counting doors and stopping. Smaller rear doors still make four. A Crew Cab listing does not state a fit for an extended cab.
- Assuming Double means one thing. ARIES files the Silverado, Sierra and 2007-up Tundra Double Cab under extended, and the Tacoma Double Cab under crew. Double cab vs crew cab goes deep on this.
- Reading Quad and Crew as the same. On a Ram they are separate listings. See quad cab vs crew cab for how they split.
- Forgetting the rest of the truck. The cab is one of the things that matters. Year does too, and so can your bed on longer boards. Bed and cab fitment explains that, and how to measure bed length covers the tape measure.
Once you know your cab
Go to running boards by truck for your year and cab, or use the picker on the home page. The how we verify fitment page explains why we quote what each listing says instead of telling you what fits. Check your exact year and cab on the listing before you buy.
Tailgate questions
Can I tell my cab type from the VIN?
Often, and it is worth trying. NHTSA's VIN decoder has a Cab Type field, and NHTSA says the data comes from the manufacturer. Its group names lump several maker terms together, like Extra/Super/Quad/Double/King/Extended, so you may still need your doors and your maker's own word to finish the job.
If a truck has four doors, is it a crew cab?
Not necessarily. ARIES says an extended cab can have smaller rear doors, and those still count as four doors when you walk around the truck. A crew cab typically has four full-size, front-hinging doors. Compare the size of your rear doors with the front ones, and see which edge they hinge on.
Is a Double Cab an extended cab or a crew cab?
It depends on the truck. ARIES files the Silverado, Sierra and 2007-up Tundra Double Cab under extended, and the Tacoma Double Cab under crew. So the name will not tell you the door layout across makers. Look at your own rear doors, and use the name your maker gives that cab.
What if the cab name on my paperwork does not match the listing?
Do not order until you have sorted it out. Listings and makers use different words, and some titles use two at once. Run the fit check on the listing, or ask the seller with your year, make, model, trim and cab name. A dealer can also look it up from your VIN.
Where this comes from
Keep reading
- ExplainerTruck cab typesThere are three truck cab types: regular, extended and crew. Each maker names them differently. See Ford, Ram, GM, Toyota and Nissan names, sizes and door layouts.
- ExplainerDouble vs crew cabIs a double cab a crew cab? On a Tacoma it sits in the crew group; on a Silverado and a 2007-up Tundra it does not. See the cab table and what it does to board fit.
- ExplainerExtended vs crew cabA crew cab typically has four full-size doors. An extended cab has smaller rear doors or a seat-forward layout. See each maker's names and why boards don't swap.
- ExplainerCab and bed fitmentCab length running boards run along the cab, wheel-to-wheel boards run to the rear wheel. How cab names and bed length decide fit, and how to read a listing title.
- How-toCheck a listing fitsCheck any running board listing against your truck in seven steps: year, cab, exclusions, part number and maker sheet. Real title traps, and what to ask the seller.
- CompatibilityAll trucksWhich running boards fit your truck depends on model, year block, cab and sometimes bed. See the splits listings state for each truck and where to start.
Who writes this
runningboardsfortrucks.com Editorial Team
Fitment, buying advice and explainers
We are the editorial team at runningboardsfortrucks.com. We read listing titles, maker pages and instruction sheets, then write down which truck, year and cab each one states and where we read it. We do not run lab tests and we do not own a test fleet, and we say so openly.
- Fit quoted from the listing or maker
- Sources and dates on every page
- No lab tests, stated openly
- Publisher details in the imprint