i know a 31x10.50x15 should fit on the 15x8 wheel with +25 offset and not rub but will they fit on a 15x7 with +38 offset with no issues? thanks for help!! :)
07-18-2013 03:15 PM
Forget you ever heard the term 'offset' for Jeep or truck wheels, that is a different measurement that is not all that useful here. The offset dimension is more useful for cars & sports cars. The measurement you want to use is 'backspace' which is a different measurement, the two terms are not interchangeable.
I have an offset to backspace converter at home but not here... do you know the backspace dimension for the 15x7 wheel? If you do know the backspace dimension, anything less than about 5.25" will work fine. Most aftermarket wheels have significantly less backspacing than that so I would guess you'd be fine.
Edit: I just did a quick calculation... a 15x7 wheel with +38 Offset has a 5.5" backspace dimension. A 31x10.50 tire on a wheel with that much backspacing would rub a tad on the control arms when the steering wheel is turned all the way to the left or right. That could be fixed by adding a washer or two under each of the two steering stop bolts.
07-18-2013 06:15 PM
thanks that answered my question completely! I'll probably end up getting a set of soft 8s to put them on
07-18-2013 09:32 PM
just make sure I'm good...the wheels I'm looking at are a -19 which if I figured out correctly it should be about a 3.75 backspace. Will that solve the rubbing without modification and not stick out very far from the flares? PA has tough inspections so I want to avoid an issue. Thank you very much for the info!
07-19-2013 12:21 AM
3.75" of backspacing means the wheel will stick out 1.75" further than most factory wheels.... that's a lot more, and not much backspacing for that 10.5" width tire. That's not much backspacing when you have to worry about the stock fender flares covering the tires well enough to pass the PA inspection. I wouldn't be optimistic with that little amount of BS.
I know you can find 15x8 steel wheels with 4.5" of backspacing, I think ProComp makes them. That'd be a more realistic amount of backspacing considering your PA inspections.