I think the biggest gains will come from those with stuck ring packs. If your car or truck is getting 3 to 4 miles per gallon less than it once did, then it is quite likely that the rings are stuck and can't work independently. Of coarse tune up parts and tire inflation can be a big drag on your fuel bill as well. Buit if you are in tune with properly inlated tires, there is a very good chance that ARX can help you get back that lost economy.
