The 1 ton dully truck i removed the motor from had a 3.54 ratio rearend and at 65 MPH motor rpms were a little high.truck had no problem pulling what ever was put behind it.so i figured 20"rims with 34"dia. tires i would be able to trailer my 42 behind with ease. the 40 has 2 speed axel thats making a lot of noise and is geared to climb mountians.
