What Size Running Boards Do I Need for a Double Cab vs Crew Cab?
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Buying running boards for a truck sounds simple until you reach the fitment options.
You select your truck model—and suddenly the product page asks:
Crew Cab? Double Cab? SuperCrew? Extended Cab?
For many truck owners, this is where the confusion starts.
A Chevrolet Silverado Crew Cab and Silverado Double Cab may share the same model name, but that does not mean they use the same running boards.
The same applies across other truck families.
That is why the most important rule when choosing running boards is:
Do not choose the board only by truck model or by its overall length. Match it to the exact year, make, model, and cab configuration listed for the product.
This guide explains why cab style matters, how to identify the correct fitment, and how current TOPBEE running boards are organized around different truck configurations.
Quick Answer: What Size Running Boards Do I Need?
For vehicle-specific running boards, there usually is not one universal board length that fits every version of the same truck.
Instead, start with five pieces of information:
- Vehicle year
- Manufacturer
- Model
- Cab configuration
- Product-specific fitment
For example, if you own a Toyota Tacoma Double Cab, look for running boards specifically listed for the Tacoma Double Cab.
If your truck is a GMC Sierra Crew Cab, use a product that explicitly lists GMC Sierra Crew Cab compatibility.
A product saying “Silverado/Sierra Crew Cab” should not automatically be treated as compatible with a Double Cab.
Fitment wording matters.
Why Does Cab Style Affect Running Board Fitment?
Running boards mount alongside the cab.
That means the dimensions and mounting locations of the cab directly affect how the board and brackets fit the truck.
Different cab configurations can change:
- Cab length
- Door arrangement
- Position of the rocker area
- Mounting-point locations
- Bracket placement
- Length and position of the step surface
This is why two trucks with the same model name may require different side steps.
The problem is not simply whether the running board is “long enough.”
The complete mounting system has to line up correctly with the vehicle.
Crew Cab vs Double Cab: Why the Names Can Be Confusing
One of the biggest mistakes truck owners make is assuming cab names mean exactly the same thing across every manufacturer.
They do not.
Truck manufacturers use different naming systems.
You may encounter terms such as:
Crew Cab
Double Cab
SuperCrew
SuperCab
Extended Cab
Quad Cab
Access Cab
These terms describe cab configurations, but you should not use one manufacturer's terminology to guess another manufacturer's fitment.
For running boards, the product listing is what matters.
If TOPBEE lists a product for a specific cab configuration, treat that configuration as part of the fitment requirement.
Is “Double Cab” the Same as “Crew Cab”?
Not necessarily.
This is exactly why ordering running boards based only on photos can cause problems.
Even when both versions have front and rear doors, the cab dimensions and mounting arrangement may differ.
A board built for one configuration may be:
- Too long
- Too short
- Positioned incorrectly under the doors
- Paired with brackets that do not match the mounting points
So the safer question is not:
“Do they look similar?”
Ask instead:
“Does the running-board listing explicitly include my cab configuration?”
If the answer is no, do not assume compatibility.
What Does “Running Board Size” Actually Mean?
When someone searches:
“What size boards do I need for a Double Cab vs Crew Cab?”
it is easy to think the answer should be something like:
“Buy a 5-foot board for this cab and a 6-foot board for that cab.”
But vehicle-specific running boards are more complicated than that.
Overall length is only one dimension.
A properly matched running-board kit also depends on:
- Bracket design
- Bracket spacing
- Factory mounting locations
- Door position
- Step position
- Cab body dimensions
That means a running board with a similar overall length can still be wrong for the vehicle.
For TOPBEE products, use the listed vehicle and cab application first rather than selecting solely by a measured board length.
How TOPBEE Organizes Running Boards by Cab Fitment
TOPBEE's current product lineup provides several useful examples of why exact cab configuration matters.
Rather than selling one universal running board and claiming it fits everything, current TOPBEE product titles identify the intended truck configuration.
Toyota Tacoma Double Cab: TOPBEE RB10
One current TOPBEE product is:
TOPBEE 2-Tier Steel Drop Steps for 2005–2023 Toyota Tacoma Double Cab RB10
The important words are not only:
Toyota Tacoma
They are:
Toyota Tacoma Double Cab
If your Tacoma uses a different cab configuration, do not assume the RB10 is compatible simply because the truck is still a Tacoma.
Verify the exact product fitment before ordering.
Internal link: TOPBEE RB10 Toyota Tacoma Double Cab Drop Steps
Chevy Silverado & GMC Sierra Crew Cab: TOPBEE RB06
TOPBEE also currently lists:
TOPBEE 2-Tier Steel Drop Steps for Chevy Silverado & GMC Sierra Crew Cab RB06
Again, the cab specification matters.
This product is presented for:
Crew Cab
That means an owner searching:
“What running boards fit my GMC Sierra Double Cab?”
should not automatically select this product simply because “GMC Sierra” appears in the name.
The current TOPBEE product title identifies Crew Cab fitment.
If your Sierra is a Double Cab, confirm a product specifically lists your configuration before purchasing.
This is particularly important because one of the questions already appearing for TOPBEE in Google is:
“What assist steps and running boards fit the GMC Sierra Crew Cab versus Double Cab?”
The answer is not to choose whichever board looks closest.
Match the product to the exact cab configuration.
Internal link: TOPBEE RB06 Silverado & GMC Sierra Crew Cab Drop Steps
Chevy Colorado & GMC Canyon Crew Cab: TOPBEE RB03
Another current TOPBEE model is:
TOPBEE 2-Tier Steel Drop Steps for Chevy Colorado & GMC Canyon Crew Cab RB03
Here again, the product title specifies:
Crew Cab
The vehicle model alone is therefore not enough information.
Before ordering, a Colorado or Canyon owner should verify:
Model + cab style + applicable fitment information
rather than searching only for:
Colorado running boards
or:
GMC Canyon side steps
Internal link: TOPBEE RB03 Colorado & GMC Canyon Crew Cab Drop Steps
Ford F-150 SuperCrew and Super Duty Crew Cab: TOPBEE RB09
Ford provides a particularly useful example because its naming convention introduces another term:
SuperCrew
TOPBEE currently lists:
TOPBEE 2-Tier Steel Drop Steps for Ford F-150 SuperCrew & Super Duty Crew Cab RB09
This demonstrates why shoppers should pay attention to the manufacturer-specific cab wording.
A Ford owner should not assume that:
SuperCrew = every four-door F-150 configuration
or that a product for SuperCrew automatically fits another cab style.
Use the exact fitment given for the product.
Internal link: TOPBEE RB09 Ford F-150 SuperCrew & Super Duty Crew Cab Drop Steps
How Do I Know Which Cab My Truck Has?
If you are unsure whether you own a Crew Cab, Double Cab, SuperCrew, or another configuration, do not guess from the running-board product photo.
Start with the vehicle itself.
Check the exact year, model and configuration through your vehicle documentation or manufacturer information.
Then compare that information against the running-board listing.
A useful buying sequence is:
Truck → Cab configuration → Product fitment
not:
Running board appearance → Guess truck fitment
This small change in shopping order prevents many compatibility mistakes.
Can I Identify My Cab by the Number of Doors?
Door layout can help you recognize differences, but it should not be your only fitment check.
Manufacturers use different cab names and body designs, and model generations can change.
That is why TOPBEE's existing installation guidance emphasizes checking:
year, make, model, cab style, and body generation
before selecting a no-drill running-board system.
The product listing should remain the final fitment reference.
Internal link: No-Drill Running Boards Guide | TOPBEE
Will Crew Cab Running Boards Fit a Double Cab?
Do not assume they will.
Even if both configurations belong to the same truck model, different cab dimensions can affect both board length and bracket alignment.
For example, if a TOPBEE product is specifically labeled:
GMC Sierra Crew Cab
that should be treated as a Crew Cab fitment unless the product page explicitly lists additional configurations.
If you own a Sierra Double Cab, look for a product that actually lists Double Cab compatibility.
This is safer than trying to modify brackets or force a mismatched board into place.
Why Bracket Fitment Matters as Much as Board Length
A running board is not installed by simply placing a long metal step under the truck.
The mounting brackets create the connection between the board and vehicle.
Those brackets need to correspond with the mounting locations on the compatible truck.
If the brackets do not align correctly, having the “right length” board does not solve the problem.
This becomes especially important with no-drill running boards.
A properly designed no-drill system is intended to use compatible factory mounting points rather than requiring the owner to create new holes simply to make the product fit.
So if a no-drill board does not match the mounting points on your truck, first question the fitment—not the truck.
Does No-Drill Mean the Running Boards Are Universal?
No.
This is another common misunderstanding.
No-drill describes the intended installation method.
It does not mean:
universal fit.
TOPBEE's no-drill running-board guidance explains that compatible systems use brackets, hardware and existing vehicle mounting locations.
But those mounting locations depend on the vehicle configuration.
A no-drill board still needs to match the correct truck.
Why 2-Tier Drop Steps Are Different From Standard Running Boards
TOPBEE's current side-step lineup uses a 2-tier drop-step design.
This gives the driver and passengers distinct stepping areas rather than one continuous flat board.
For taller trucks, a lower step position can make entry and exit easier while maintaining a more rugged truck-oriented appearance.
But design preference comes after fitment.
Before deciding whether a 2-tier step is right for your driving needs, first make sure that the product actually fits:
your truck + your cab configuration.
Internal link: 2-Tier Drop Steps vs Running Boards | TOPBEE
Crew Cab vs Double Cab for Daily Driving
If both configurations have compatible running-board products available, the board choice should still be based on the exact vehicle.
From there, you can consider how you actually use your truck.
For a daily driver, running boards may be particularly useful when you frequently enter and exit the vehicle.
For family use, easier access to front and rear seating can make the step a regularly used part of the vehicle.
For work trucks, repeated entry and exit throughout the day makes step placement and a stable stepping surface especially important.
For a taller truck, a drop-step design can also reduce the step-up distance between the ground and cab.
But none of these benefits matter if the mounting system does not fit the vehicle correctly.
What If I Use My Truck Off-Road?
Drivers who use their trucks away from pavement should think about more than appearance.
Running-board design affects the space along the lower side of the truck.
A lower drop step can make cab access easier, while its position should also be considered in relation to the terrain you normally drive.
This is why there is no single answer to:
“What are the best running boards?”
Daily commuting, family use, work sites and rougher terrain may lead to different priorities.
Fitment should still remain the first filter.
Internal link: Best Running Boards for High Trucks | TOPBEE
Common Mistakes When Buying Running Boards
Mistake 1: Shopping by Truck Model Only
Searching:
“Silverado running boards”
is not enough.
You still need to confirm the truck's year and cab configuration.
Mistake 2: Assuming Crew Cab and Double Cab Are Interchangeable
They may belong to the same model family, but that does not guarantee identical running-board fitment.
Follow the exact product application.
Mistake 3: Choosing Based Only on Board Length
Similar length does not guarantee compatible brackets or mounting positions.
Vehicle-specific fitment matters more than one overall dimension.
Mistake 4: Assuming Four Doors Automatically Means Crew Cab
Manufacturer terminology differs.
Verify the actual cab configuration instead of relying on a visual guess.
Mistake 5: Assuming No-Drill Means Universal
No-drill running boards still use vehicle-specific brackets and mounting locations.
No drilling and universal fit are two different concepts.
Mistake 6: Ignoring the Cab Name in the Product Title
When a listing says:
Double Cab
Crew Cab
or:
SuperCrew
those words are part of the fitment information.
Do not treat them as marketing text.
How to Choose the Right TOPBEE Running Boards
Before ordering, work through this sequence.
Step 1 — Confirm the Vehicle Year
Vehicle generations can change mounting locations.
Step 2 — Confirm Make and Model
For example:
Toyota Tacoma
GMC Sierra
Chevrolet Silverado
Ford F-150
Step 3 — Confirm Cab Configuration
Determine whether the truck is:
Crew Cab
Double Cab
SuperCrew
or another configuration.
Step 4 — Match the Exact TOPBEE Product Listing
Do not select a product simply because it fits another version of the same truck.
Step 5 — Review Installation Requirements
If the product is designed as a bolt-on/no-drill system, verify your truck is included in the listed fitment before installation.
Step 6 — Decide Whether the Step Design Fits Your Use
Once compatibility is established, then consider:
daily access, truck height, work use, passenger access and the type of driving you normally do.
Current TOPBEE Fitment Examples
Here is a simple way to understand the current TOPBEE lineup:
| TOPBEE Model | Listed Vehicle | Listed Cab Configuration |
|---|---|---|
| RB10 | Toyota Tacoma | Double Cab |
| RB06 | Chevy Silverado / GMC Sierra | Crew Cab |
| RB03 | Chevy Colorado / GMC Canyon | Crew Cab |
| RB09 | Ford F-150 / Super Duty | SuperCrew / Crew Cab |
The important lesson from this table is simple:
TOPBEE running boards are not organized only by truck brand.
They are organized around vehicle fitment.
Frequently Asked Questions
What size boards do I need for a Double Cab vs Crew Cab?
Do not choose only by an overall running-board length.
For vehicle-specific side steps, match the product to your year, make, model and exact cab configuration.
A board listed for Crew Cab should not automatically be considered compatible with Double Cab.
Will Crew Cab running boards fit a Double Cab?
Not automatically.
The cab dimensions and mounting locations may differ.
Use the product's stated fitment instead of assuming the two configurations are interchangeable.
What running boards fit a GMC Sierra Crew Cab?
TOPBEE currently lists the RB06 2-Tier Steel Drop Steps for Chevy Silverado and GMC Sierra Crew Cab applications.
Verify your exact vehicle fitment on the product page before ordering.
Does the TOPBEE GMC Sierra Crew Cab board also fit Double Cab?
The current RB06 product title identifies Crew Cab fitment.
Do not assume Double Cab compatibility unless it is explicitly listed for your exact product and vehicle configuration.
What TOPBEE running boards fit a Toyota Tacoma Double Cab?
TOPBEE currently lists the RB10 2-Tier Steel Drop Steps for 2005–2023 Toyota Tacoma Double Cab.
Drivers with another Tacoma cab configuration should confirm a compatible product rather than assuming the RB10 fits every Tacoma.
Is Ford SuperCrew the same as Crew Cab?
Ford uses manufacturer-specific cab terminology.
For TOPBEE fitment, follow the actual listing.
The current RB09 product identifies Ford F-150 SuperCrew and Super Duty Crew Cab applications.
Are no-drill running boards universal?
No.
No-drill refers to the installation method, not universal vehicle compatibility.
The brackets and factory mounting locations still need to match your truck.
How do I know whether my truck is Crew Cab or Double Cab?
Verify the exact configuration using your vehicle's official information rather than relying only on appearance.
Then compare that configuration with the running-board product listing.
Final Answer: Fitment Comes Before Size
If you are searching:
“What size running boards do I need for my Double Cab or Crew Cab?”
start by changing the question slightly.
Instead ask:
“Which running boards are specifically designed for my exact truck and cab configuration?”
That leads to a more reliable answer.
For vehicle-specific running boards:
Year + Make + Model + Cab Style + Product Fitment
matter more than simply choosing a board because its overall length looks correct.
TOPBEE's current lineup shows this clearly.
The Tacoma RB10 is identified for Double Cab.
The Silverado/Sierra RB06 is identified for Crew Cab.
The Colorado/Canyon RB03 is identified for Crew Cab.
The Ford RB09 is identified for F-150 SuperCrew and Super Duty Crew Cab applications.
Match the product to the truck first.
Then choose the step style that best fits how you actually use your vehicle.
Internal CTA: Explore TOPBEE Running Boards & Side Steps