How to Measure a Wheel Base

The wheelbase is the distance between the centers of the front and rear tires on road and rail vehicles. It’s important to know your vehicle’s wheelbase in order to have the right types of parts installed, such as fuel pumps. Fortunately, all you need to measure the wheelbase of your vehicle is a steel square, some chalk, and a tape measure.

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Part 1

Part 1 of 2:

Ensuring an Accurate Measurement

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1
Park the car on a level surface where it’s less likely to roll. Ideal locations include paved driveways and garages on flat, level ground. Set your parking brake before exiting the vehicle to best prevent it from rolling.^{[1]XResearch source}
- Parking on a driveway will also make it easier for you to make markings on the ground later on.
- If you’re measuring the wheelbase of a rail vehicle, leave the vehicle on the tracks and apply the brakes to keep it from inadvertently moving.
2
Make sure the wheels are straightened out. Straighten your turning wheels so that they are pointed directly forward. Your front and rear tires should all be parallel to each other, as well as to the rest of the vehicle body.^{[2]XResearch source}
- Most likely, your turning wheels will just be your front 2 tires. Use the steering wheel to turn these tires until they’re neatly aligned with the rest of the wheels.
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3
Look on the door sticker for the factory wheelbase first. The sticker on the inside of the driver door will include the factory specifications for the vehicle, including the wheelbase. Knowing this figure will allow you to compare your own measurement to the factory’s and gauge whether you’ve taken your measurement correctly.^{[3]XResearch source}
- The wheelbase will be indicated on the sticker by the letters “WB” followed by a number. This number will be the measurement of the wheelbase in inches.
- If you need to know your vehicle’s wheelbase in order to purchase replacement parts, this is the best way to get an accurate measurement.
4
Identify the center of your tires to know where you’ll measure from. This is usually the spot in the middle of the lug nuts or screws holding the tire in place. The wheelbase is the distance between the centers of the front and rear tires of both road and rail vehicles, so you’ll need to measure from 1 center to the other to find the wheelbase.^{[4]XResearch source}
- If your vehicle has more than 2 axles (e.g., an 18-wheeler), the wheelbase is considered to be the distance between the steering axle and the center of the driving axle group.
- If you’re measuring the wheelbase of a rail vehicle, locate the points where the wheels contact the rail instead of the center of each wheel. The wheelbase of rail vehicles is measured between these locations instead of the wheel centers.

Part 2

Part 2 of 2:

Taking the Measurement

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1
Place a steel square on the ground and align it with the center of the tire. Place the short end of the steel square or framing square on the ground. Slide it along the ground until the long end is aligned directly with the center of the front tire.^{[5]XResearch source}
- For best results, align the opposite edge of the long end (i.e., the edge further away from the short end) with the center of the tire.
2
Mark on the ground where the square aligns with the tire center. Use thick chalk to make a mark where the bottom of the long end meets the ground. Pull the steel square away and make the mark slightly thicker so it’s easier to see.^{[6]XResearch source}
- Don’t make the mark too thick or draw it out as a line. This may actually make it more difficult for you to accurately measure the wheelbase. Stick to a thick circle no larger than ¹⁄₂ inch (1.3 cm) in diameter.
3
Repeat this process with the rear wheel to make a second mark. Use the steel square and chalk to make a mark on the ground where the center of the rear axle is. Make sure your marks are both on the same side of the vehicle.^{[7]XResearch source}
- You should now have 2 marks on the ground: 1 for the steering axle and 1 for the rear axle.
4
Use a tape measure to determine the distance between these marks. Place 1 end of your tape measure on the mark by the steering axle and extend the tape down to the mark by the rear axle. This length is the wheelbase of your vehicle.^{[8]XResearch source}
- Note that this measurement is typically recorded in inches.
5
Repeat this process on the opposite side of the vehicle. It’s important to determine whether the wheelbase is the same on both sides of your vehicle. If the wheelbase is longer on 1 side than on the other, this will cause the vehicle will drag to the side and may even pull the rubber off of your tires.^{[9]XResearch source}
- You can take your vehicle in to many body repair shops to have the wheelbase altered.

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How do I choose a rim without affecting the car's performance?
Nick Psaros
Automotive Expert
Nick Psaros is an Automotive Expert working to encourage people to become car enthusiasts and share useful automotive content with people around the world. He has spent the past six years building an online following and community dedicated to automotive excellence. He has a follower base of over 10,000 YouTube subscribers and has garnered over 1 million views on his channel.
Nick Psaros
Automotive Expert
Expert Answer
Selecting rims for a car requires thoughtful consideration of various factors, with the initial step involving a clear definition of your specific objectives. For example, truck owners must decide whether they desire a lowered or lifted appearance and whether off-roading capabilities are a priority, each of which has implications for the suspension system. Likewise, for car owners, the preference for large, shiny chrome wheels with a classic appeal is common. However, it's crucial to grasp that the installation of oversized wheels can impact both the vehicle's aesthetics and driving dynamics. The reduction in tire sidewall height, for instance, may create the perception of a higher suspension, influencing the car's handling in unanticipated ways.To ensure that the choice of rims does not adversely affect car performance, it's essential to carefully evaluate how specific rim characteristics align with your intended goals. Consider factors such as the overall weight of the rims, the impact on suspension geometry, and the potential alterations to the car's handling dynamics. By balancing aesthetic preferences with an understanding of the technical implications, you can make an informed decision that enhances the visual appeal of your vehicle without compromising its performance.
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