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Discussion Starter #1
thinking about just going down to a 235/85 -16 tire size. im running 35's right now and love them but only get like 17 or 18 mpg with them. any thoughts, will it help that much?
 

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im runnin 33-12.50-16.5 " and i love them.
 

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plvaulter06, you runnin 35 MT's? What kind?
 

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Have you checked your speedo & trip meter for acuricy? that can make a bid diffrence in milage! On my truck for every 100 miles on the trip meter I have aculy gone 113 miles. You may be getting better milage than you think.
 

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ya my spedo is off by about .87 to 1. I get like 15.5 by the speedo
 

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Im hoping smaller tires and timing up to 20* and ill be back well over 20. $4.37/gal is seriously killing me. im sure you guys are mad also, but it is so stupid, seriously
 

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I ran 235x16`s on my `97 with 4.10`s for 9 years. Can`t tell you about real mileage as I only used the overhead during that time. The tires were good, as far as I`m concerned. Never could get more than 28,000 miles out of them though.
 

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I run the 235/85 16's on both my trucks, and they both have 4.10 gears. I average 16-17 mpg too. I don't know if it would be benificial to you to run the smaller tire because it will raise your RPM's on the top end therefore resulting in more fuel useage. Just my opinion!!
 

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:agree2::agree2:
I run the 235/85 16's on both my trucks, and they both have 4.10 gears. I average 16-17 mpg too. I don't know if it would be benificial to you to run the smaller tire because it will raise your RPM's on the top end therefore resulting in more fuel useage. Just my opinion!!
:agree2::agree2: In town it may help tho. But not on the HWY.
 

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I used to Run 35"s as well but as soon as the fuel prices started to jump I went down to a 285/75/16 and so far i've gone from the same 17-18 on the freeway to 22 or so and they arent a bad looking size either. maybe another size option to look into.
 

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i run them on my truck though its a first gen and 235/85/16 is actualy the stock size i like them never realy had a prob get pretty good milage with them too
 

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I just put a set of 225 80 17's on my truck today used my flash pac to change the computer to 28.75" tire height (they are acually 30" tall) to hopefully drop my rpm's and improve mileage on my 06 dually.
 

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Just my opinion but the only time (to a certin extent) a larger tire will hurt your milage is in stop and go trafic or stop light to stop light in town driving. I run 37" tires with 3.55 gears and on the HWY can get 19-21+ running 75-80 MPH.
 

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I'm running 235/85-16's on my truck. Last tankful, with 1/3 qt. of Lucas, I got 17.5 mpg (hand calculated with 7% added to odometer; stock tires were 215's, and the speedo's off a bit).
 

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305/70r16 3.53 gears last tank was right at 17 with a quart of two stroke oil 1450 rpm =55 mph
 
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