Hi

Im puting on a 6" lift and 35" tires on my 09 ram 1500. I tow a pop up trailer that has a spot for my ATV on it. I need to know if i need to change gears? If i need to what type of gears should i run? Im a newbie when it comes to this stuff. Gears in it now are the 3.92

Please help

Thanks

 

The 35" tires will change your "effective" ratio to about 3.70. I'm guessing that your trailer and ATV weighs in less than 3500 lbs.

My 'opinion" is that you will be just fine especially in consideration of the fact that the pop-up trailer does not produce much wind resistance.

 

Trailer weight is 2545lbs and my ATV is 700. This not include me putting gear in the truck or in the trailer. Coolers , Kids ATV weight 200lbs , generator etc...

Hope its good dont want to spend more money right now. Im up to 5600 with everything .

 

I have a 3.55 gears and was up to 13,000 lbs last week. Didn't break any land speed records but got 11.8 MPG cruising at 55-60mph on a 25 mile trip in the hill country.

Don't toucha nuthin'.

 

what do yall think about 34s and 3.55 gears?

 

The 34" tires will change your "effective" ratio to about 3.36

Good MPG flat land cruising at 75-80. Not as good as the 3.21 guys but close.

 

What is the math to figure out the effective ratio. I have been wondering this as well. Will I be ok running 35's on a 3.55 with a 4' lift. I don't want to spend the money either!

 

This is a simple formula to get a close approximation of how tire size changes effect the drive ratio. The exact method requires another factor in the formula (final drive ratio of the top tranny gear) but the simple formula works fine.

Effective gear ratio = (OEM standard tire height / replacement tire height) x (actual rear gear ratio)

Note: I use an OEM standard tire height for the 2009-2010 Ram 1500 of 31.6" (17" wheel and 265/70/17 tire)

Therefore for 35" tires:

31.6 / 35 x 3.55 = 3.21 effective ratio

 

Thanks. So IYO will I be good if I am towing a 4,000lb trailer up and down mountian passes? Why would be the reason for switching out the gears.

 

The truck should do it but you may be down as low as 2nd gear on long steep grades at 45MPH. Someone with 3.21 gears needs to answer that one.