should i regear 2011 ram 1500?

[tw11ram]

I have a 2011 Ram 1500 4.7L 4x4 with the 3.55 gearing. The truck initially came with 265/70/17's which I have changed out to 285/75/17's. I took a trip recently that I've taken with the old size tires. (450+ Miles 1 way) I expected a decrease of MPG's and acceleration, however it destroyed the MPG's more than what I was expecting on the trip and going up the slightest of hills the truck wants to downshift constantly to make it up the hill when only at ~2kRPM.

From what I have read, if I re-gear I should increase the gear ratio by the percentage difference with the new tires. Is this something that I should look into doing to compensate for the new tire size?

 

[Socalramfan]

What ratio are you thinking of?

 

[Joshua Collins]

A regear could help but more than likely cost would take awhile to recoupe the gas savings. I would say you lost more than expected due to im would assume the new tire is a lot heavier than what they replaced. When changing tire size a lot of people do not figure in tire weight from one company to another or between load ranges. The extra rotational mass kills mpg.

Also did you program for the new tire size? This effects transmission shift points which can cause a fairly decent drop in mpg if not done and hurt performance.

 

[metalchewy]

My 2010 4.7 came with 392s, my tires, a little shorter than your 75s at 285 70 17s. Planning to take it up to 34" tire when i level it.

Gas mileage isn't great either. It's a truck. 19mpg on highway and 16 around town. I've had worse mileage than this in a number of other trucks.

10-11mpg on E85. .

On the hills, I learned to just reach over and hit the Tow button as I come into it, so it doesn't wait until it has to downshift to keep the speed constant. Seems to help so it doesnt downshift two gears without it.

Unless you plan todo the gears yourself, there's a fair chunk of change to be spent to change them over ...

 

[tw11ram]

The gear ratio i was thinking of going with was either a 3.90/3.92 or a 4.10/4.11

I did program the tire size into the truck and got the Speedometer Accurate. and turning on the tow/haul mode i did think about doing it, but never did. i will definitely try that on the way back.

the Maximum i got on the trip was 13, but would sit around 12.

I'm not opposed to doing it myself or getting someone to do it. I've looked at the Yukon Gear's and they seem to have a good rep, I'm just only finding the rear gearing for my truck since i would assume that both front and back have to be done. It might be something that I am missing when searching for the gears. I don't know if i need to be gearing up or gearing down..

 

[Socalramfan]

If your only going one step up, might not be be a justified cost.

Im at 3.92, and am in the process of evaluation the gearing as well. For me….. I’d consider 4.5 etc. in your case, I’d be looking at 4.1 for starters.

Did I misread….. ? Is yours a 2wd or 4wd?

Reach out to CheechDogg.on37, he’s done the mod and can give you actual feedback

 

[tw11ram]

i will look into 4.10/4.11 regearing. it is a 4WD, 2011 Ram 1500 4.7L SLT Quad Cab TRX4.

i will reach out to him to see if he can give any feedback on it.

 

[CheechDogg.0n37s]

I wouldn't regear unless you were going up to a 35 inch tire then the 4.56s would be perfect ...but to just jump up to even 4.10s not even worth it man, the size in tire is not going to affect anything with the 3.55s, save your money

 

[RamminMopar]

4.56 if you're planning to keep it awhile otherwise save your money

 

[Burla]

Totally regear, my biggest mistake was getting these damn 3.55's to be honest. Bought a sale truck, didnt do my do diligence. Go above 3.92's either way, ask the shop if cover or diif needs to shaved to get the 4.56 in there, I believe the 4.11's will go in. see what the cost will be if there is a difference. Nobody that has ever gotten 4.56's regret it as far as performance, you may not like the mileage, but that truck will get moving. I'd probably build up that valve body as well, you probably will have to one way or another, but get that thing shifting faster and firmer.

 

[tw11ram]

Thanks, I'll look and see about the 4.56's as well. I do plan to keep this truck as long as I can since it is a super reliable truck that hasn't had any major issues. if i do end up regearing it, i'll probably spring and get a limited slip/locker for it as well.

 

[RedSRT4Me]

I'm on Team Regear to your driving style!!
The more aggressive driving styles require shorter ratios.

First determine the size of tire you'll always run. Me 37/4.56. Then search out the regearing charts and see where your setup falls.

In my opinion 35's and 4.56 will be too short for the newer 8-speed trucks while it could be perfect for the 6 speed.

My favorite part of the regear is not needing to downshift in any gear with the new setup. If you want to accelerate in 8th? No problem. Uphill?no problem. Takes significant stress off the trans and puts it at the axle. Side benefit most don't mention.

 

[Socalramfan]

I'm on Team Regear to your driving style!!
The more aggressive driving styles require shorter ratios.

First determine the size of tire you'll always run. Me 37/4.56. Then search out the regearing charts and see where your setup falls.

In my opinion 35's and 4.56 will be too short for the newer 8-speed trucks while it could be perfect for the 6 speed.

My favorite part of the regear is not needing to downshift in any gear with the new setup. If you want to accelerate in 8th? No problem. Uphill?no problem. Takes significant stress off the trans and puts it at the axle. Side benefit most don't mention.

Well said

 

[tw11ram]

Looking at a size to gearing chart, should i be going off what the supposed size is for a 285-75-17 (33.8in or 2697mm) or go off what i programmed in with AlfaOBD to get the speedometer accurate, 265-75-17 (32.6in or 2604mm). would i round up to a 34in tire on the chart or use 33in tire on the chart. the chart that i am looking at is on 4WP's site and the 34in tire to 4.56 is in the bottom of the red, while the 33in tire is not even in the band. or should i not even worry about the bands of performance/economy provided? i dont believe im going to go any bigger with the tire as with no lift/level its stuffed in already and doesn't rub under normal conditions (i have gotten it to rub when in a turn and hitting a decent bump/pothole). even once it is leveled its still a bigger tire than what was factory and what was installed on my step-father's 2018 Rebel(not by much tho....). even if i did go with a bigger tire in future, if i still did a 4.56 it looks like i'd have some room to increase tire size afterwards without having to re-gear again. sorry if this sounds like a stupid question.