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Discussion Starter #1
Has anyone tried this with 37's. I currenly have a Fabtech 8" lift, Pro Comp 37's with factory 3.73's and I was thinking about regearing but do not know if I should go with 4.30's or 4.56's.

I drive 70HWY/30City and would like to get some of my power back but do not want to go with to low of a gear that my mileage goes any further south than it already is. I guess my biggest concern is knowing what RPMs I will be running while doing 70mph.

Any help or results of similiar situation be would be greatly appreciated.
 

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Has anyone tried this with 37's. I currenly have a Fabtech 8" lift, Pro Comp 37's with factory 3.73's and I was thinking about regearing but do not know if I should go with 4.30's or 4.56's.

I drive 70HWY/30City and would like to get some of my power back but do not want to go with to low of a gear that my mileage goes any further south than it already is. I guess my biggest concern is knowing what RPMs I will be running while doing 70mph.

Any help or results of similiar situation be would be greatly appreciated.
4:30's with 37's would put you close to what you are running stock with 3:73's......4:56's would give little more low end power, but yes your mileage and RPM's would suffer
 

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i would go with 4.30's. I did.
with 4.30's you can still get a Ford 4.30 and wont have to go aftermarket. IMO Fords gears can take more abuse.
 

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Discussion Starter #4
Thanks guys!!! That's what I was thinking. I'm not sure I could find anyone that would install Ford gears for me other than Ford. Or should I just have Ford put them in. My apologies for being so ignorant, I am pretty new to the differential stuff. In addtion, would should I expect my mileage to do with the 4.30's vs the 3.73's.

BTW, this forum and it's members kick ARSE :clap:
 

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I had a local gear shop install my 4.30's (Dana front and Ford Sterling rear). Any gear shop should be able to install the Ford gears for you. If they can't find a new shop, because you don't want that one working on your truck anyway.
 

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i am wanting to do the same thing. i am running 37" tires and was thinking about regearing to 4.30's. does anyone know if my truck being a manual transmission will have any different effects than say a truck that is an automatic? thanks for the help.
 

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I have 37's and have also considered installing 4.30s. I would suspect that MPGs may increase when towing also. What do you think/what have you experienced?
 

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