Gears: thinking of switching from 410 to 456?

[Lifted_Stroker]

My truck is currently equipped with 410 gears, i`m also rolling on 36" super swamper raidials which seem to lug the truck alittle bit. The truck likes to down shift alot when the cruise is set or even when i come up to the slightest grade. I have been told that I can run 456s and still have driveabialty and also pull my 24' enclosed trailer, I realize that my fuel mileage will drop, but i didnt buy this thing to get great fuel mileage. Does any one on here have these gears installed in a 250-350? I hear they come stock in a 450-550? how well do you like them and how bad did it really drop you r mileage? thanks

 

[97CREWCABPSD]

im runnin 4.88s with 37s. i personally think you would be happier with 4.88s than 4.56s because there isnt much diferrence in 4.10s and 4.56.

 

[Lifted_Stroker]

488s huh? I have also had that mentioned to me. how does it run with 488`s?
what rpm do you turn at about 70-75 mph?im all for it as long as it isnt over 2500 rpms at about 75 mph.???

 

[97CREWCABPSD]

i think im about 2350-2450 rpm doing 70-75 and the power is awsome

 

[Lifted_Stroker]

well that seems reasonable, i just dont want it to absolutely scream while im doing 70 you know. Do you ever pull any thing with it? if so i imagine it does pretty well? oh 1 more thing does it like to down shift alot or the gears and your ats take care of that?

 

[97CREWCABPSD]

yeah i pull... i haul in my bed a polaris predator quad that weighs 450lbs 40 gals of race gas, tools, ramps, firewood, plus my diamond plate tool box full...then i pull my 28' travel trailer that weighs about 8000lbs i hit the scales around 23500lbs and push the big hills around here 70-75 no problem it down shifts once and a while but it does not hunt at all.

 

[AdamBomb]

I have 4.30 gears in my F350 and am running 40" tires. I don't know my RPM's at 70-75 because my speedo is so off from the tires and gears. If you all ready have 4.10's I wouldn't switch to 4.30's because its is such a small change you will barley be able to tell. 4.88's would be nice, very creapy crawly

 

[Maintain]

4.55's would actually increase your gas mileage (slightly) because it returns your truck close to its original gear/tire ratio (if it was 3.73). 4.88's would be like having 4.10's with stock tires. 4.88's will tow somewhat better, but the 3.55 will get better fuel economy and you can have an overall higher speed. Honestly, after re-gearing a few trucks I feel it's always better to be just a tad undergeared then over geared. There is nothing worse then being maxxed out at 65-70mph and getting 10 mpg.

 

[HTRDDSL]

I have 4.30 gears and am running 37 inch Goodyear MTR's. Actual height is about 36 inches. I'm running just under 2200 at 70 MPH.