4.10 highway rpms

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bloombloom88

bloombloom88

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2009
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4.7
i have 4.10s and 285/75s(about33s) and am at about 2100 rpms at 70... Its hard to say a 33's are 33 inches because most are + or - a few tenths(32.6 or 33.4, for an example) which can make a difference when you have tires at each end of that difference. Hope that helps you

Thanks for the info. I'm getting answers anywhere between 2000-2200 rpms so that gives me a good idea what to expect. I just wonder how much my highway mpg will go down with 4.10 and going from a 31in tire to a 33in
 

Firehawk

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Formula: Since we have no idea what tire size you are running we will assume 33's, at 70mph freeway speed, in 5th trans gear which we know is .67 ratio.

3.55 (gears) x 70 (mph) x 336 = 83496
83496 / 33 (tire size) = 2530
2530 x .67 (trans OD ratio) = 1695.22 RPM's at 70 with 3.55's

4.10 x 70 x 336 = 96432
96432 / 33 = 2922
2922 x .67 = 1958 RPM's at 70 with 4.10's

Not a very big jump IMO. I personally run around 2200 RPMs at 70 with my truck and in no way will I ever "run out of gear".

There ya go!

Thanks
 
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