I call bs on 24mpg lifted truck with 36's. That dude should have stayed in school. Oh unless it was a kick ass tailwind or downhill all the way, then 24mpg still does not count.
Pro and cons for dropping to 3.42 gears
- Thread starter KevinD
- Start date
I call bs on 24mpg lifted truck with 36's. That dude should have stayed in school. Oh unless it was a kick ass tailwind or downhill all the way, then 24mpg still does not count.
I don't think he would lie to me, he had no idea what to expect when he picked the truck up, and I didn't say anything about him possibly getting better mileage VS. the Banks tuning, which I normally see getting good mileage on stock LLY's. I hand calculated that other truck I did years ago with the 6sp conversion to get 23mpg driving 100 miles round trip daily to the owner's job site for a couple months straight. The anomaly trucks are out there, I've had some really good ones come through and some really bad ones. I wish I could make some of the bad ones into good ones every time but they just don't cooperate like that all the time. 
Yeah. My tires are 34" tall. But seriously thinking about dropping back down to stock height. I drive to much on the interstate. Ha! So the height of my tire plus the weight of my 20's isn't helping me one bit. But I would like to keep my 20's would it help if I went back to stock height and width of a 245/75/16 what ever size that is in a 20? Blank/blank/20
I noticed my tires said 275/60/20's it's my bad on that part they are 275/65/20's
I noticed my tires said 275/60/20's it's my bad on that part they are 275/65/20's
It would help spool I bet. Probably be more fun to drive with those gears. Definitely would take a load off the drivetrain
I'm not sure mines a manual my 6th is .72:1
I think the allisons final gear is different
Probably would be more fun but then again right now I'm looking for mpg. If it would help. Sure I would go that route. If not. Just gonna drop back down to stock height tires. Still trying to figure out if it will be the same on my 20's or just going back to straight up stock.
Going to a narrower tire would help. The heavier whell/tire combo hurts acceleration, but once your up to speed it is mostly just rotating mass along for the ride(it does hurt you some having extra rotating mass, but not tremendously). It's the wider tire that hurts more than anything else. The wider tire creates more drag due to the extra friction from the wider contact patch.
I just done all the calculations on my gears. If I drop back down to stock tires with the same running gear with 5th being .71 at 65 I will run 165 more rpm than I do now with 34's so hoe would it make me get better mpg with dropping back down to stock tire size???