Originally Posted by 75F350

Its all about the backspacing. You will require a set of wheels with 3 3/8" backspacing or less. Many companies offer 3" as well as 2.75" backspacing.
Failure to find the right wheel with the correct backspacing will result in clearance issues.


Here is a 42" tire on an 8 lug 15" wheel:




Its the right way to do this. You do not want to waste money on spacers. This can be a problem, and after the cost of the spacers are realized, you will have more than the total cost of the correct wheel.


*Note* this is for steel wheels. Aluminum wheels are to thick at the bead for this measurement, and will require more backspacing which is not all that common, and may be too much for the bearings.