gears?!

Well, i hear an awful lotta good about them. specials the 4.56's But i have a few questions. WOuldnt 4.56's make your truck run at a higher rpm on the highway? and burn more fuel? I thought the lower the # the lower rpm u were at like a better cruising gear would be 3.73's as oppose to a 4.56
i have a 3.92? i think and if i were to do the 4.46's wouldnt that kill what mileage i got left

I always thought the same but from what I have read is the engine has less load on it with the 4.56s... Im waiting for my factory rear to go and do both front and back at the same time.

Gears are the single best improvement your can make to your truck. The rule is if you are running 33" or bigger tires use 4:56. Shorter tires use 4:10. 4x4's need matching gear sets done together at the same time. The better gearing allows the engines to run with less load. 70+ mph highway running will couse a slight loss in MPG. Town driving you will pickup some MPG. The added performance and fun factor will hurt your overall MPG because you won't be able to keep yourself from spanking the sedan's at the lights. I have 4:10's with 30.5 inch tires and wish I had gone with 4:56 instead. Good luck.

4Wheel Parts has a great gear chart. It shows based on gear and tire what your RMPs should do @ 65 MPH

Lift Kits, Tires & Wheels by 4 Wheel Parts

On the 45RFE & 545RFE 3rd gear is the 1.00:1 gear. Which of course no one drives in @ 65 MPH but it shows how it effects the RPM's.

if you ever plan on running a bigger tire, go 4.56. if not, consider going 4.56 anyway. most people wish they had just done 4.56 from the beginning. as stated, it wont hurt your highway mileage at all unless you go over 70.

4.56 should have been a factory option. the hemi engine just does much better power and efficiency-wise at higher rpms. Down low it hurts tryin to get big quad cabs moving and the keep them moving. with 3.55 certainly, and even 3.92 to an extent, theres a lot of work on the engine just to keep it going. the 4.56 eliminates a lot of the strain. the point of all that is even though you're running higher rpms, the engine is working significantly less.

In town you'll see an easy 20% gain in fuel economy. You'll also see 100% more grins from yourself, and 100% more "wtf?!?" looks from other vehicles you just spanked off the line

I went from 3.55's to 4.10's wishing i went to 4.56's. Now i may have a chance to get my old 4.88's back so i might go right up to that.

Like Nick says.

DONT FEAR THE GEAR.

or something like that.

i wish i would have went 4.88 instead of 4.56. gains all the way around, performance, and mileage wise. i can still get 17-18mpgs on the fwy on long trips in my heavy ass 2500. dont fear the gear.