A 235/75 15 tire is approximately 29.9". Going to a 31" tire will make your new final gear ratio a 3.68 and you will gain 2mph@55mph. Your speedo will read 55mph and you will actually be doing 57. You'll lose mpg slightly in stop and go traffic with 1" larger tires and gain mpg on longer speed sustained runs. At least that's the what the tire and gear conversion tables show. All of that factors with the weight of the old tire vs. the weight of the new tire and how close each one is to the stated tire size. Allot of tires say 31" but are either a little taller or a little shorter.
1995 SWB 300 I6, M5OD, 273 gears, 235/75r15's, 21MPG, 50" Led Light Bar, 6" Off Road Lights, Full Synthetic Fluids, K&N RF1012
"Gentlemen, we can rebuild them. We have the technology. We have the capability to build the world's first unstoppable truck. The F-150 will be that truck. Better than it was before. Better, stronger, faster."
well if i could choose the best tire I would grab a wrangler mtr, its durable and they have kevlar in the side walls. but since i am also on a strict budget i have to settle for the cooper tires, but its still a good tire. and its within a small budget. costs about 380 for two tires to be installed at big o.
I an considering leveling my 95 2wd with f250 front coils. When I first got the truck I was only getting 12 mpg and now after a tune up and some cleaning I am up to 16.2. My? Is would leveling the front and putting on some 31's really affect my mpg's? Thanks for the help
Leveling won't effect your MPG, but the tires will. I noticed I lost 1 entire mpg when I went to 31s. But I also have 3.08 gears so you shouldn't even notice it
1991 F150 XLT Lariat - 300 I6/E4OD, 2 Wheel Drive, Bright Regatta Blue Metallic
Mods: True duals, 55w AUX reverse lights, Smoked tails/reflector, Smoked corners, 31x10.50s, 15x10s, Blacked out grille, Diamond plate bed rails, Tampa Bay Rays fuzzy dice, 2.5in level, 2in rear block, 6,000K HIDs, LED grille lights, Custom clear headlights
Update! Springs ordered. Got them for $78 shipped of Ebay. Should be getting them put in next weekend. I thought since I was in there I would replace all tie rods and adjustment sleeves. Can anyone give suggestions on what brand or parts stores to look at as far as quality steering parts. I don't want to old junk with new junk. 5.0 2wd. Thank you
Coils are in. Finally got around to replacing the stock coils and what a difference. The moog cc844 coils raised the front end almost 2in and improved the ride quality immensely. Great improvement. One last? On this issue. I know I can fit 31x10.5 but I can get a set of 31x12.5 for free from a buddy. Will they fit without rubbing or are they too wide? Thank you all for your replies