Am I measuring this right in the pics ? I saw a few posts where others thought the oem 20x8.5's were either 5.5" or 6" back space, but I took a wheel off yesterday and measured 6.5".
Am I doing it right with the straight edge - referencing the inside edge of rim ?

 

I am not wandell but I can answer your question. Yes your factory rim has 6.5 inch backspacing and you are measuring right.

 

He is right, the 20's got 6.5" the rest are less than that.

 

It's the 17s and 18s that are 5.5"

 

thanks guys.

 

RIght.