gear ratio
New User
Joined: Sep 2002
Posts: 17
Likes: 0
From: Ogdensburg, US
gear ratio
i need help, i want to know the rearend gearing of my 86 ford f-150, it has the 5.0 efi 302 in it. it has a 3spd aod. it is bone stock, also i would like to know what rearend would be the best in gas mileage. this truck is driven about 40 miles a day, and i need the best mileage possible. 10-12 just isn't cutting it!!!!
thanks
ford rules!
thanks
ford rules!
Laughing Gas
Joined: Apr 2001
Posts: 1,024
Likes: 0
From: Elon, NC
gear ratio
Hey tuff, welcome to FTE.
If you'll look on the driver's side door frame you should find an ID tag with quite a lot of info. On the bottom row you will see the printed word "axle" with a code typed underneath it. Your owner's manual will decode that for you. If you don't have a manual, post the code here and we'll decipher it for you. There also should be a metal tag on the differential that tells what the gears are.
Ron
If you'll look on the driver's side door frame you should find an ID tag with quite a lot of info. On the bottom row you will see the printed word "axle" with a code typed underneath it. Your owner's manual will decode that for you. If you don't have a manual, post the code here and we'll decipher it for you. There also should be a metal tag on the differential that tells what the gears are.
Ron
Post Fiend
Joined: Nov 2002
Posts: 9,987
Likes: 7
From: Memphis, TN
gear ratio
H in the first position of the axle code means limited slip "Trac-Lok" differential; 1 means open diff.
8 in the second position means 3.08 ratio; 9 means 3.55; 5 means 4.10; 6 means 3.50.
8 in the second position means 3.08 ratio; 9 means 3.55; 5 means 4.10; 6 means 3.50.
Laughing Gas
Joined: Apr 2001
Posts: 1,024
Likes: 0
From: Elon, NC
gear ratio
[updated:LAST EDITED ON 05-Nov-02 AT 01:30 PM (EST)]Great info Steve, thanks for picking up my slack.
Tuff, I'm confused on which tranny you have though. Is it the AOD (automatic overdrive)? Or a spd manual with overdrive (which is what my truck has). There's a couple ways to go as far as gearing to change your fuel mileage. A lot depends on what you use your truck for. If it's mainly a daily driver that sees a lot of highway use, but not used for hauling or towing heavy, then higher rear gears will get you better mileage. Something in the 2: 75 to 3:08 range. You can also go to a taller tire to accomplish a similar change. Remember though, the higher the gear the less your engine is turning at highway speeds. A high revving, relatively low torque engine like the 302 will suffer performace-wise from too tall a gear. If you do have an overdrive tranny, something in the 3:25 to 3:55 range gears is what I'd want. If you dont have OD, then definitely the 3:08 range is gonna be better economy wise.
If you DO work this truck hard, or tow heavy with it, those 3:08 gears are gonna be harder on your truck because loaded it's harder to maintain the revs that 302 needs.
Consider how you drive the truck, what you want from it, and work from there.
Good luck,
Ron
Tuff, I'm confused on which tranny you have though. Is it the AOD (automatic overdrive)? Or a spd manual with overdrive (which is what my truck has). There's a couple ways to go as far as gearing to change your fuel mileage. A lot depends on what you use your truck for. If it's mainly a daily driver that sees a lot of highway use, but not used for hauling or towing heavy, then higher rear gears will get you better mileage. Something in the 2: 75 to 3:08 range. You can also go to a taller tire to accomplish a similar change. Remember though, the higher the gear the less your engine is turning at highway speeds. A high revving, relatively low torque engine like the 302 will suffer performace-wise from too tall a gear. If you do have an overdrive tranny, something in the 3:25 to 3:55 range gears is what I'd want. If you dont have OD, then definitely the 3:08 range is gonna be better economy wise.
If you DO work this truck hard, or tow heavy with it, those 3:08 gears are gonna be harder on your truck because loaded it's harder to maintain the revs that 302 needs.
Consider how you drive the truck, what you want from it, and work from there.
Good luck,
Ron
