i got a 99 srx and i run a 1.5 inch with 144 studs down the middle. now keep in mind i had to shave the tunnel protectors in half,put front and rear heat exchanger protectors on, notch the track where the protectors are and run my track a lil tight but it is awesome in deep snow. ive put about 2100 miles on it like this with no problems. and yes i have 9 tooth drivers