I have a 2001 Dodge 2500 Super CabV-10 Auto with 3.55 gear DANA 70 in the rear we are pulling a 35 foot Fifth wheel Travel Trailer that weights 12000 LBS the truck pulls it very badly no power, I want the put some lowwer gears in it to get it to wake up and pull,I was thinking 4.56 what do you think, to low or I should be ok with 4.56 it's a every day driver mosty HWY speeds.

We use to have a Diesel Dully with 4.10's in it it pulled great I know the V-10 not a Diesel Dulley but I thoght it would much pull better.

 

4.56 would be a big difference but it you do mostly highway it might be a bit much. 4.10s would be great but its up to you.

 

yah the 4.56 will be good for pulling but itll suck back the gas with out the traler on there, how big of tires do you have, if there still close to stock id recoment 4.10 as well