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Discussion Starter · #1 ·
Im trying to decide between running 35s and 37s in a Toyo open country m/t. Im averaging about 20 mpg(hand calced) now. Im curious what the mpg loss would be with 35X12.50 or 37.13.50 if the difference between the two isn't that much id rather run the 37s

thanks, J-Mo
 

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cruising down the freeway mine went up because it dropped my rpms!!:thumbsup
 

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Im running 37's and geting anywhere from 14-16 in town/ hwy about 18-20
 

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35's for in town 37's highway . I had 35's i got about 16-17 in town
, highway was only about 17-18 , Once i got my 37's i checked it 18.5 in town 21-23 highway . That was after my programmer and speedo recalibration . All was hand calculated :thumbsup
 

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with 35"/37"s you speedo will read 65, in actuality you are moving at 70-72, which is in the sweet spot of 1600 - 1800 RPMS.
 

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bigger tire bigger mass, more mass more power to get moving, so like stated above, smaller tires for more town driving, bigger tires for more highway driving.
 

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on my truck according to my gps the speedo was off 13 mph!!!:thud:
 

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on my truck according to my gps the speedo was off 13 mph!!!:thud:
How fast were you going that it was off though???? Either way thats a huge gap.
 

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the faster you go, the more the speedo will be off.
 

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With 37s my speedo is off 14.5%. Best I have ever got w/stock tires is 16mpg highway. Yesterday got 14 mpg highway w/ 37s. All hand calculated.
 

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my intown is horrible now since adding my 37s.... havent really calculated anything... I actually seem to be doing better the little i have drivin it on the highway.. 70 mile round trip everyday to work gets a little expensive so i dont drive the truck much.. Ill have to get it out and do some calculations...
 

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37s put my speedo off by 10 mph at 80, and with 4.10s I'm going around 75(65 on the dash) at 2000 rpms.
 

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best i've ever got with my 37's was 15mpg and that was pretty much highway, but driving around 75-80mph with my 4.10's


edit with 4.10's either way the mileage sucks lol
 

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When my dad got the truck, i wish he woulda got the 3.55 insteda the 3.73 oh well 20/20 hindsight.
 

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Yeah, I just went to 37's from 35's and seems like mileage went down, 62 mile's a day to work gets pricy! Cant wait for it to cool down so I can get back on my bike. I haven't calculated the ratio i'm off now.
 

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You will get a bit worse in the city. But out on the HWY its like having a little taller gears IMO. In my truck on the hwy crusing between 75-80 MPH with 3.55's & 37" tires I get any ware from 19-21. But in order to get correct MPG you will need to take in to concedration your trip meter will be off so you will need to figure out by how much it is off by. In my truck I have to multiply what ever the trip meter says by 1.13 to get the correct milage. For every 100 miles shown I have aculy gone 113 miles. And that makes a BIG diffrence when trying to figure MPGs.
 
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