If you’re buying new rims for your MiniTruck, you will need to know it’s offset and how it affects your particular truck.

The offset of a vehicle’s wheel is the distance between the centerline of the wheel and the plane of the hub-mounting surface of the wheel. It is typically measured in millimeters. Wheels are usually stamped with their offset such as “ET45” for a 45mm offset.

Offset has a significant effect on many elements of a vehicle’s suspension, including suspension geometry, clearance between the tire and suspension elements, the scrub radius of the steering system, and visually, the width of the wheel face relative to the car’s bodywork.

Learn how to calculate wheel offset

1. Determine the wheel backspace: Lay the wheel face down and put a straight edge across the inboard flange. Measure the distance from the rule to the hub mounting pad in inches. Your result is the wheel backspace.
2. Measure the width of the rim: Measure from the outboard flange to the inboard flange. Write your answer in inches.
3. Calculate the center line: Take the width of your rim and divide by two.
4. Subtract the center line from the backspace: For ex. If the center line was two inches and the backspace was 1 inch the offset would be positive one inch.Conversely, if your center line is greater than your backspace you will have a negative offset.

After calculating your current wheel offset, use this neat tool from 1010tires to see if your new wheel will have fitting issues.