A trick I use is to take a Q-tip and break off the cotton swab end, making a small ball. I then dip it in white paint [ or any type marker liquid] and stick one in each tires thread. Then I drive the car on a blacktop drive a little over one tire revolution.
You now have 4 sets of distance marks on the driveway. They should all match closely. The advantage to doing it this way is you get the actual rolling circumference of the loaded tire on that car.
This is also a good trick when doing calculations for speedo and gear changes.
Usually one will find that problem to be a simple difference of tire PSI..
[ which changes the rolling circumference]