I would go 1/8" as well, just be sure to check it correctly.
Lift the front tires off the ground and scribe a true center line around the diameter of each one.
Have the truck on level ground and roll it forward at least one tire rotation or more.
Let it come to a stop with out using the brakes or rolling backwards.
Measure the rear of the tire at the the same hight as you do at the front of the tire, and measure as high up on the tire as possible.
Have the same person hold the tape each time and the other read the tape.
This will give as close to a driving measurement as you can get.
Joe
