How to Measure Your Truck Bed Length Before Ordering Wheel-to-Wheel Boards

You only need this for parts that run past the cab. Cab-length boards follow the cab and wheel-to-wheel boards run on to the rear wheel, so bed and cab fitment is the place to start if you are unsure which you are buying. The method below comes from LINE-X, a truck-bed coatings company, and it was written for bed covers. We found no running board maker that publishes one. A tape reading does not prove anything fits. It tells you which of the maker's labels is yours.

What you need

A tape measure, and your paperwork or window sticker for the year, cab and bed name. Pen and paper beat memory here.

The steps

1. Check whether you need the number

   Look at the part. If it is a cab-length board with no bed in the title, you do not need it. If the title or fit table names a bed or says wheel to wheel, carry on.

2. Clear the bed floor

   Take out loose cargo so the tape can lie flat. Note any drop-in liner or mat, because it sits between the tape and the floor.

3. Lower the tailgate and find your start

   LINE-X says to lower the tailgate so you measure from the correct starting point, the inside edge of the tailgate.

4. Run the tape to the bulkhead

   Extend the tape along the bed floor to the inside edge of the bulkhead, the wall closest to the cab. Keep it flat and straight.

5. Write it down in inches

   Note the figure in inches, along with your year, cab name and the bed name from your paperwork.

6. Match it to the maker's bed label

   Find the row for your year and cab in the maker's table and read its bed labels. Pick the row your bed belongs to, and ask the seller or maker if it is not clear.

Why your number won't match the name

Bed names are labels. LINE-X says Ford often labels beds by approximate length and the actual measurement can differ. Ford's 2026 F-150 sheet gives the inside length at the floor, so you can see the gap for yourself.

Those are Ford's figures for one truck and one model year. They say nothing about a Chevy, a Ram or an older F-150.

Makers label the same bed differently

This is the trap on wheel-to-wheel parts. Read November 2, 2026, from two maker documents. LUVERNE's guide is its 2023 catalog, so its year rows stop earlier than Westin's.

Look at the Silverado row. One maker writes 5.5 feet and the other 5 feet 9 inches for what look like the same short-bed trucks. We do not know why, and we are not going to guess. Now look at the Ram row. "5.7ft" and 5'7" look alike and are not the same number, and "6.5ft" and 6'4" sit side by side for what look like the longer beds. So copy the label from the table you are buying from, and do not convert it or carry it over from another maker.

Common mistakes

• Measuring along the bed rail. Ford's figure is at the floor, and the LINE-X method runs along the floor too.
• Mixing feet and inches. See the Ram row above.
• Using the reading to decide fit. Bed length alone never settles it. Year, cab and sometimes fuel type sit in the same row. LUVERNE's table has a fuel column, and it splits some Silverado 2500 HD rows by it.
• Assuming an older truck matches a new one. Rows change by year, as F-150 and Ram 1500 show.

Once you have the label, head to wheel-to-wheel running boards. The last step before ordering is how to check a listing fits. How we treat all of this is on how we verify fitment, and the home page has the truck picker.