I was reading on some past posts and some of you said you were getting better gas mileage with 4.56 is this true and also how is it acceleration wise. Also how much does it cost to have these installed as I would not be able to do it my self. I see many of you have new gears and was just wondering mainly if the better mpg's is true since I am getting about 12.3 according to the computer.

 

you will improve mpg in city mostly and more power off the line acceleration. more higher gears means more rpm traveling 65. i am sure that other member will respond since some do have these gears and never regret it. i may be not right but this is showing idea.

for example, with 3.92 gears, traveling 55 mph that hits top gear rev @ 1500 rpm. with 4.56, 55 mph top gear rev @ maybe around 1800 to 2100 rpm

 

yeah ive been wondering something similar. Does the 4.56 gears make you shift gears at a higher rpm or lower?? Cause my understanding is that its higher, and i dont know how that would result in better gas mileage. But im probably wrong.

 

If you do a lot of highway driving and you're worried about mpg's I wouldn't get lower gears due to running at higher rpms. Some say the city mpg will improve due to less load on the engine needed to accelerate...I never noticed it with my maro and 4.10's.

A full tune-up will help your mpg more than anything...that includes all drivetrain filters and lube.

 

As a general rule you'll pick up about 1-2 mpg in city/town driving and lose about the same on the interstate. But like any mod that will save you an mpg or two, the roughly $1500 COST of this mod will take you 20 years or about 800,000 miles to make up for it in fuel savings. Gears are a performance thing and with larger than stock tires, IMO worth every penny.
If you want to see significant gas savings DON'T BUY A TRUCK!!!

 

Yes, 4:56 gears have a greater mechanical advantage in moving a large QC truck.
But the flip is, at speed on an interstate where your already moving and up to speed for long periods of time at high MPH, this becomes a disadvantage as your turning higher RPMs thus drinking more fuel.
You gotta' think of your driving style and where you do most of it.
In the city/stop start and wanting to get off the line quick............I'd say get her done!
On the freeways, leave at 3:55 or slighly higher like me.
AL.

 

Agreed - if you want a race truck (or just fast off the line) the gears are good. I have the 3.21 gears.....very nice on the freeway, but not exactly speedy gonzalez off the line...LOL

But it still runs good. And no, you don't get a truck if you are worried about mileage. My wife drives a 2007 Suburban! We ain't no tree huggers!!

I just run over Prius and the like....Hah.

 

what do
GM and Ford
think about
differential gears in pickups versus better MPG?

https://dodgeforum.com/forum/off-brand-news-concepts-and-rumors/172127-xfe-silverado-with-6sp-3-08-a.html

notice the 3.08 and 3.15 diff ratios AND the higher tow ratings

Here on Dodgeforum
I put in writing
an offer to bet "Pinks Style"
$30,000 put up in advance as a Cashier's Check
that two otherwise identical
Rams except for 4.56 and 3.21 diff ratio
put through the
Goodyear San Angelo TX test track
using the
SAE/TMC Type IV
"Gold Standard"
MPG test
using independent drivers
and completely videoed
so forum members like yourself could watch it in the future
would show the
3.21 Ram getting better MPG than the 4.56

Air_Ram would not take me up on this offer
and judging from the above weblink about GM & Ford
and also that Chrysler now offers the 3.21 on the 2009 Ram 5.7
no engineer at any of the world's
15 major auto company would either

but what do they know

 

The right way to do it
Goodyear goes by the book with Fuel Max test

When Goodyear introduced its new Unisteel tires with Fuel Max technology last year, and claimed that they were more fuel-efficient than its older designs, the company invited the press to come to its San Angelo Proving Grounds in Texas and observe an SAE/TMC Type II fuel consumption test, pitting old against new.

In this case, two identical tractor-trailers — a control rig and a test rig with the same powertrain, mileage, horsepower, GCW, tires, pressure, etc. — were fitted with removable, portable fuel tanks, which were weighed before and after identical runs of at least 28 miles at the exact same highway speed. Fuel consumption was measured by tank weight, and the two rigs were compared as a baseline. Three runs, which must produce results within 2 percent of each other, were made. In this case, the two rigs’ fuel consumption figures were consistently within 1 percent of each other.

Next, the test was repeated, with the control rig unchanged, and the test truck fitted with the component to be tested — in this case, the new tires. Over the course of three runs, with results within 2 percent of each other, the test truck had consumed about 7.5 percent less fuel per run.

Claim made, point proved, case closed.

 

Hank since you have never attempted to do a gear swap you clearly have no idea what the results would be... And its clear your MATHEMATICALLY CHALLENGED! Sure you can cut & past the math of others to support your THOUGHTS but thats all they are... thoughts. The best you can do is CUT & PAST the experience of somone else.... LOL

Fact is you continue to disagree with EVERYONE who has real world results... So as far as your concerned EVERYONE who has moved from 3.55's to 4.56 gears has been lieing... Only because there factual results did not back up your own theory.

Please Hank, tell us what gears you have installed on your 3rd Gen Ram... Tell us how they worked for you... tell us the MPG gains/losses you experienced.... Tell us something YOU HAVE DONE to your OWN 3rd Gen Ram that would add incite to the subject. Please dont post somone elses experience... post your own... if you have any at all.

We just want to hear what you have experienced.... Now every time I ask this question to you... you tap dance around it and NEVER answer it... I would like to see you answer this one this time.

SPEED SAFE, AIR RAM