That is very tough to answer as it depends on many factors, but you do not need to spray that much product onto the wheels.
A little really does go a long way. If I were to give an estimation, you should be able to wash 16-20 wheels(four wheels 4-5 car washes) with one bottle.
If it doesn't end up working, or you don't get as many applications as you expected, don't worry about it! We are so confident in everything we sell, every product is backed by our Zero Risk Policy. Use the product once, or use the entire bottle.