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nathan01xl · 11-02-2013, 04:09 PM

Been a while since i felt inspired to do any ecomodding. Been averaging 36 on my commute, on winter gas, so i have been feeling pretty good about that.

BUT I have an itch to mod something right now and I am leaning towards regearing. Right now I running 3.73 gears with 215/75r15s, and my best idea so far is to try and grab a 3.08 rear end out of an 1992 ranger, which is also 1" narrower on each side, and go with some 195/65r15 LRR tires (Michelin Energy Savers A/S??). By my calculations that should be 17.4% decrease in RPMs from the gears, and a 10.5% increase from the tires. Combined this should result in a 6.9% decrease in cruising rpms, with far less rolling resistance. It should also make it much easier to do a rear wheel skirt with the wheels sitting an additional 1" inboard.

Any idea what i can expect from this gearing change? I am expecting a couple MPGs highway, but dont want to cripple my trucks 4 cyl. Is there any research about ideal % change or am I going to need and just figure it out as I go?

11-02-2013, 04:09 PM	#1 (permalink)
nathan01xl EcoModding Apprentice Join Date: Jun 2013 Location: pdx Posts: 153 The Long Ranger - '01 Ford Ranger XL Pickups 90 day: 28.68 mpg (US) EcoSI - '08 Honda Civic SI 90 day: 28.83 mpg (US) Thanks: 5 Thanked 37 Times in 26 Posts	Regear possibilities (01 Ford Ranger) Been a while since i felt inspired to do any ecomodding. Been averaging 36 on my commute, on winter gas, so i have been feeling pretty good about that. BUT I have an itch to mod something right now and I am leaning towards regearing. Right now I running 3.73 gears with 215/75r15s, and my best idea so far is to try and grab a 3.08 rear end out of an 1992 ranger, which is also 1" narrower on each side, and go with some 195/65r15 LRR tires (Michelin Energy Savers A/S??). By my calculations that should be 17.4% decrease in RPMs from the gears, and a 10.5% increase from the tires. Combined this should result in a 6.9% decrease in cruising rpms, with far less rolling resistance. It should also make it much easier to do a rear wheel skirt with the wheels sitting an additional 1" inboard. Any idea what i can expect from this gearing change? I am expecting a couple MPGs highway, but dont want to cripple my trucks 4 cyl. Is there any research about ideal % change or am I going to need and just figure it out as I go?