Is this recommended for a 2wd with 22's on it? Will my MPG go up?

 

Will the 4.56 gears work in a rearend that has the 3.55 gears and limited slip right now? What all will I need to change? The truck is a 02 Ram 1500 with the 4.7L engine, auto tranny.

 

Personaly I recomend it for ANYONE who drives a 3rd Gen Ram with the 45RFE/545RFE transmission and a tire hight of 30"+.

SPEED SAFE, AIR RAM

 

So when you go to build and price a Ram at the dodge website they tell you right on the website that: "A numerically lower axle ratio results in lower engine rpm and better fuel economy. A numerically higher ratio improves acceleration, climbing grades, carrying loads or pulling a trailer." in the section where you choose the gear ratio. This seems to contradict what's being said here, weird. I realize that a higher gear ratio is the lower number, but they say numerically explicitly.

 

There is NOTHING you need to do after the gears are installed... the SPEEDO does NOT need to be recalabrated because the signal is taken from the ring gear on the rear gear.... You may want too look into a stronger carrier if you have the cash... the stock unit 9.25 does not have the best track record and even I had to have mine replaced under warranty because a clutch pack retaining clip went south and fragged the rear end. I plan to upgrade to a powertrax unit ... but to answer our question.. NOTHING is NEEDED, but its good insurance. Im running the stock carrier wth MOTIVE 4.56's... so far no problems.

SPEED SAFE, AIR RAM

 

I would also like to know where to get these.

 

Well the are right if you where driving a 3,000 pound car with dinky 24" tall tires and no overdrive. BUT our trucks weigh 6,000lb's+ and we have 30"+ tall tires and a super super overdrive of .67.......... They are using yesterdays theory of opperation where it was good then... but it does not apply in our set up.... for the fact we have 30+ inch tall tires, 6000 pounds to move and maintain speed of a brick wall, and a .67 overdrive which literally tames the 4.56s down to a streetable GRANNY gear.

At 60MPH, I only gained 300 RPM's from the 3.55 to the 4.56's..... "THREE HUNDRED RPM's" BUT better, I gaind "mechanical advantage" which helps move the truck from a dead stop with less effort (less fuel) and it in a higher power band at 60MPH which gives it better fuel economey. sure the RPMs went up but the load on the engine went down... and the load on the engine has a greater effect on fuel economey than RPM's alone...

So YES THERE SITE IS WRONG! Poeple with the 3.92's report the same and in most cases BETTER fuel economey than those with the 3.55's! AND even better.... those with the 4.56's report the same and in many cases better fuel economey than those with the 3.92's...



SPEED SAFE, AIR RAM

 

OO, nifty stuff. Good to know.

 

ok i do a whole lot interstate driving and i got 24 inch heavy as hell wheels. i am thinking of going from 3.55 to 4.10 just because of the highway and interstate driving. does this sound good cuz the only intown driving i do is to and from work and maybe the shop (barn) i work at after work at times. i got a 02 ram with the killer V6 (ya i know right) and the auto trans. only have a worthless jet chip and a k&n intake. scared of getting a exhaust till i get my new motor put in after i blow this 6 cyl.

 

Go fo it. With 24" tires though you may think you little engine is revving kinda high but I don't think it will be too bad.

Rough guide and formulas. Does not have a 24" pizza cutter though (LOL)
http://www.s-series.org/htm/calc/ratiotable.htm