Installing new rims is an easy way to make your vehicle stand out from the rest. But, the purchasing process can sometimes be a bit daunting. Two of the most commonly unknown aspects when buying a brand-new set of wheels are the offset and backspace measurements. And, as luck would always have it, they’re the two most important measurements when selecting wheels that will actually fit your ride.
Here, we explain what offset and backspace actually mean, as well as what to look for when measuring.
Offset is the distance from the center of a wheel to its mounting face (see image for reference).
- With a higher offset, your wheels mount farther inward, providing greater clearance between the outside edge of the tire and fender, but less clearance between the inside edge of the tire and your vehicle’s suspension
- With a lower offset, your wheels mount farther outward, providing a wider vehicle stance. For example, a lifted truck with oversized tires often requires 25mm-50mm (approx. 1-2”) less offset than stock, so the wheel and tire are farther toward the outside. This provides more clearance from the suspension. Some lifted trucks even require a zero or negative offset rim in order to clear large tires
- It’s important to check with your installer before purchasing to ensure that the wheels you order provide the proper offset to give you the look and clearance you need
Backspace is the distance from the inside edge of a wheel to the mounting face. A wheel’s backspace is equal to ½ the wheel’s width + offset (in inches) + ½” (see image for reference).
- More backspace indicates that the wheel protrudes further into the wheel well and closer to the suspension parts — which increases the risk of rubbing
- Less backspace indicates that the wheel protrudes less into the wheel well and therefore reduces the risk of rubbing
- Lifted trucks and SUVs often have a maximum allowable backspace pre-specified by the lift kit manufacturer. With too much backspace, your wheel or tire won’t fit your lifted truck or SUV
- Few trucks accept more than 5” backspace. Less than 5” backspace is more common on lifted trucks, but confirm with your lift kit manufacturer to be sure
- Check with your installer prior to purchasing your wheels to ensure you are ordering the proper backspace for the look and clearance you need