Probably a dumb question but what effect does backspacing have on wheel choice? Is this just the distance between in the far inside of the wheel and the back where it attaches to the hub? Thanks for the help.

 

The way I understand it, (and I am sure I will be corrected if I am wrong)
the lower the number the farther out the wheel will stick. So a wheel with 2 inch backspacing sticks out farther than one with 4 inches of backspacing. Also, not sure about this but the farther out the wheel sticks the more stress it puts on ther components. My new wheels had 4.5 inches of backspacing, and that seems perfect to me, but that is JMHO

 

You both have it right. The correct backspacing is critical to tire and wheel fitment. Too little backspacing and the tires stick out the wheelwells and rub on the bumper and fenders. Too much backspacing and the tires will rub on the frame and swaybar.

 

Geez, something else to consider now.

On 22" rims using 305/45/22 9.5" to 10" tires, how much backspacing would be optimal for the 2005 Ford STX 4.6L? I definitely don't want that skateboard look, and I definitely don't want it rubbing on the frame or fenders, especially when turning and going up the driveway, like my last truck. YUCK!

What do the PROS recommend?

 

^Same question goes for the 05 FX4. I was figuring about 4.5 inches of backspacing should be sufficient for some 17 x 10 w/ 35's and a leveling kit.

 

My 22x9.5 Eagle's have 6.7 inches of backspacing. The stock backspacing on the 04-05's is 5 1/2 inches. I would try to stay close to that. A 17x10 with 4 1/2 inches of backspacing is gonna stick way out.

 

Here's a pic of the fitment on my Expy.

 

Your expy rim/tire setup is exactly the look and profile I want on my truck. Under the fender and no skateboard look.

 

Thanks!