xsports33

iTrader: (1)

I've been researching a lot about the re-gearing, but i had a few questions i'm hoping you all can shed some light on.

I'm debating about getting 4.56s or 4.10 During the winter i don't tow that much, but take long highway road trips to the mountains to go skiing and snowboarding. So i do a fair amount of climbing up the hills. But, during the summer i tow a lot (a 3,500 lbs boat). However, when i am towing it's usually long highway road trips to the river or the lake and some, but few, hills.

I know going with a high gear ratio will help with towing power off the line and climbing hills? But, going at ~75mph and towing down the highway i'd already be in overdrive. So wouldn't i be hurting my MPG by having a higher gear ratio considering i wouldn't "need" more towing power at 75 MPH, just to get it going. During the winter, granted i'm not towing as much but my bed is loaded with a lot of snow gear so i'm hauling a bigger load.

What would be the best for my application? As much as i would like more towing power, my towing consists of highway driving. Would the ability to have more towing power help me during highway driving and not compromise my MPG?

With all things being equal, driving style, ambient temp, octance, etc. How much of a MPG difference at highway driving is there between 4.10 and 4.56?

I also have a 6"lift with 33" tires. I plan on getting some 35" when i run down the 33's. TIA!

LesPaul

4.10 is going to suck ***** on the highway..... go 3.73 IMO

joehawkz71

iTrader: (2)

i think since your looking for better gas millage stick with the 4.10's....before i did all my engin mods when i was doing 75mph i was at about 2500 rpm's or so.... at 63-64 mph i was about 1900-2000 rpm and thats where your going to get your best gas millage....

so i guess since most your miles are going to be highway if you want to re-gear get some 4.10's just my 2 cents

PMCSPIDER

iTrader: (1)

I have 35's uner a 6"SL+3"BL, I plan to run 37's when they run out. Should I too go twith the 3:73 gears? I always thought 3:56's were the staple ratio. And just for a review someone give (in a nut shell) how #:## works again in regards to tire diameter.

LesPaul

sorry.... you are 100% correct.... i have a problem with skimming post and missing vital information a taller tire is just like putting in a taller gear.... with 35" tires or bigger i would actually recommend 4.10's.... otherwise the truck is going to suck bad down low

xsports33

iTrader: (1)

Thanks for all the quick replies. Do you guys know some real numbers as far as MPG goes between 4.56 and 4.10?

So you guys think 4.56 is overkill for 35" tires and mostly (80%) highway towing? My "truck guy" is telling me to get 4.56s for the most towing power, but i don't think he's taking into account MPG and the fact that most of my driving is highway.

joehawkz71

iTrader: (2)

last long road trip i took when i was hauling a pop-up camper i got 13.5 mpg ad that was averaging 70-75 mph ( this was done before my engin mods) and i had 35" tires and 4.56 gears 6" lift and 3" body....

i would say 4.10 cause most of your driving is going to be on the highway!



35" tires and 4.56 gears put you 5% over stock.....so that means your going to get up and go a little better then you would have stock if you had 31" tires and 3.73 gears

tkaiser36

I would have to vote for the 4.56 with 35" tires should put you just over stock plus a little some to make up for the weight of the tires.I went with 4.88 with 35" and am very happy.but i had 4.10 stock. good luck p.s lots of websights have gear ratio guids to help you find proper gearing when changing tire size,and show economy vs performance.try 4wheelparts.com click on tires then click gear ratio guide.

xsports33

iTrader: (1)

You guys aren't going to believe this but i just checked my window sticker AND called chevy and they confirmed that stock gears for my truck, which i still have, is 3.42

No joke, I really have 3.42 I was wondering why i have to floor it so hard to get up and go when i'm towing. Unbelievable!!!

joehawkz71

iTrader: (2)

very true...on the web site...and the 4.10's i think are going to keep his rpm's down when hes up around 75 mph....