would like to know what size off set i should get. o4 xb with 2"drop
would like to run 18"s

 

It all depends on the width of the wheel. I would go with a minimum of +35 on a 7.5" wheel in order to TUCK. If you want to be "flush" you can run less.

I just installed 18x7.5 Konig Next with +45 offset on the wife's xB. In the rear we also added the OTG spacers. Everything fits like a charm at stock height and I don't forsee any problems even with a HUGE drop.