My 02 V10 X towed my 35ft 9300lb loaded TT with no issues. I did swap from 3.73 to 4.30 which mde a huge difference in towing. After that the final thing I did was get custom tunes from 5 star. between those 2 things alone it really woke up the V-10! it sounds like you have 3.73`s. the 3.73`s are good fot running around empty with the kids, but not for towing. I never had a problem running the posted speed limit up a mointain. in fact I could accelrate up the mountain around slower moving traffic!
