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Discussion Starter #1
ok so i went from stock rims and tires to 35-12.50-20 and my gear was 3:73 and if you go the math with the tire size it brings it down around a 2:95 and the truck is a dog now would going up to say a 4:56 help gas milage or hurt it im just thinking yes it should hurt it but it would get it up to speed faster and in over drive quicker kinda the same reason a tuner on tow mode helps im thinkin anyone have a deff answer not just what it should be or asumptions :confused013:.... thanks
 

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i would stay with what you got........4.56 is way to low for only 35's. i ran 3:73 with my 35/12.5/20s an had no problems....
 

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with oversized tires lower gearing will help mpg. not sure about 3:73 with 35-12.50-20. fill out your truck info in signature. for mileage id go for gearing where at 65 mph your around 1800 rpm. that will keep a good power range for most towing
 

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Discussion Starter #4
its a 04.5 2500 mbrp exhaust and cold air kit with the bully dog pmt on tow mode i got around 20ish mixed driving good but not that carefull w/ stock tires.. now im luck to stay at 17 if i drive real light on the trottle. i know the tires will slow it down and lower gas milage but it takes a long time to get into over drive and the rpm stay up longer till it hits over drive im thining thats were im wasting gas between the two its only a 200 or so rpm diff i know in a normal car it would be that way but this truck weighs so much... just pondering
 

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4.10's would do you fine.
 

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I had an 07.5 w/ 3.73's and put 35's on it with no issues what so ever. Have you adjusted your speedo via the computer to make sure the truck knows your runnning 35's? That could be why your mileage dropped. Mine actually went up! Bigger tires mean more ground covered per rotation. Speedo, unless corrected will show less miles than actually traveled.
 

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Discussion Starter #7
yea i ajusted the speedo with the bully dog and it worked but gas was still down highway was at 24mpg now 18-19 with higher gear you would figure it would be better they are open country m/t tires not that aggresive.... sucks but well worth the looks
 

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4.10s is what I am soon going with on my 04.5 with 20's, wraped with 35" toyo mts..
 
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