I am about to purchase a set of American Racing Mojave wheels. They have the following specs:

size: 18x9.5
offset: -24
Backspacing: 4 1/4
Lug pattern: 5-135

I understand all the other numbers, but what is offset? Some websites seem to think these wheels wont's fit with that offset...I thought that was just how big of an outer lip the rims had. Thanks.

 

They will fit. Offset and backspacing are two different ways of measuring the same thing. Offset is how for the mounting point (where the wheel bolts on) is from the center of the wheel. For instance, an 8 inch wide wheel with 0mm offset would also have 4 inches of backspacing.