Hey all was just wondering if anyone knew if one could get away with 30/9.5/15's on a stock '89 XJ w/o worrying about the tranny or messing with the speedometer? thanks
The speedo will be off by a little (read lower than actual speed by a few MPH) but otherwise it'll be fine...maybe a little down on power than before, but not enough change to warrant a regear.
FWIW I ran 33" with stock 5-speed gears (3.07:1) for a few months and that really liked a regear, but it wasn't undrivable that way.
I'm running 30s and really don't notice a diference... I even drive the girlfriends stock XJ and then get it mine... no real noticable difference. you'll be fine!