Bronco Forum - Full Size Ford Bronco Forum banner

1 - 20 of 20 Posts

·
Registered
Joined
·
439 Posts
Discussion Starter #1
Which would be better for gas milage! Ya, I know it's a BKO and there is no such thing, but I going to ask anyway.

As of right now I will going with 6" lift. and 4.56 front/rear, and want to know which would be optimal with the 4.56 gear for better gas, 33" or 35" tires.
 

·
Registered
Joined
·
1,615 Posts
i dont think with 4.56 gears you are going to save gas with either tire size.
 

·
It's BTW Not AKA!
Joined
·
5,353 Posts
i dont think with 4.56 gears you are going to save gas with either tire size.
I promise you a truck with 35s and 4.56s will get better mileage than a truck with 35s and the stock 3.55s. Other wise, why regear?
 

·
Registered
Joined
·
439 Posts
Discussion Starter #5
I promise you a truck with 35s and 4.56s will get better mileage than a truck with 35s and the stock 3.55s. Other wise, why regear?
I have 3.55 now! Will be regearing very soon to 4.56's. This is a DD for a few years. Then it will be mainly for fun!:rockon
 

·
Premium Member
Joined
·
3,988 Posts
My (4" lift, 33" tire) truck has been running much more efficiently after my 3.55 to 4.56 gear change. 3.55's made my truck work way to hard with my 80% low end daily driving and off roading. 4.56 gives me much more efficient power in the city and no more slow down on cruise control through the mountain passes.

IMHO, 4" lift = 33" tires and 6" lift = 35" tires, both requiring 4.56's. With these tire sizes, you will not be happy with 3.55's as your power band will be dramatically different than with your stock tires.
 

·
not banned
Joined
·
5,970 Posts
with a given gear ratio, i am not sure i see why one tire size would be more gas effecient then another. unless you make the case that the larger tire has more friction because it is wider.

am i missing something?
mj
 

·
It's BTW Not AKA!
Joined
·
5,353 Posts
If I knew i were staying with 33s I would regear to 4.10s
 

·
Registered
Joined
·
2,393 Posts
try to keep your rpms around what factory is at cruising speed. (65mph @1800rpms) this will help with mpg

taller tire= lower rpms on hwy, will suck the gas down in city.

smaller tire= lower gas on hwy, higher gas in city.

gearing is about the same. 3.55 will suck in town with 35's.

my setup
4.10 with 32 = 17-21mpg on hwy/ 14-18 in city.
 

·
Registered
Joined
·
1,615 Posts
i switched over to 31's on my dd, i have a 92 that is a trail truck 37 boggers. i have 4.56 gears for that. is this not enough? sorry 4 highjack
 

·
Registered
Joined
·
439 Posts
Discussion Starter #13
I will mainly city driving, 44 miles round trip to work. I was thinking when I regear in about 2 months to go with 33", until I retire it as a DD. Then go with 35". But can not do that till spring when I will put a 6" lift on.

Then, I just keep wondering if I should go with 35" and not worry about it. Yea, that most likey the best.

mickaila, 33" would be a little lighter, thats got to count a little bit.
 

·
Registered
Joined
·
2,393 Posts
mickaila, 33" would be a little lighter, thats got to count a little bit.
what the tread rated at. agresive tread usally get worse mpg (friction) atleast on my rig they did
 

·
Registered
Joined
·
405 Posts
Keep in mind that some trucks came with an option of 4.10 gears with 235's. This might make the 4.56 sound not-so-low when you're slapping on 33's or 35's. I'll be going with 4.56 and 33's for my truck shortly.
 

·
Registered
Joined
·
1,252 Posts
I'm gonna run 4:88's for my bronco with 36s.
 

·
MARBLE GARGLER!
Joined
·
11,873 Posts
Doesnt it depend on the motor too ? you guys have 5.0 AND 351 ci motors-
 

·
Registered
Joined
·
439 Posts
Discussion Starter #18
Let me say it this way. With the way my BKO came out of the factory, 235's, 351, 3.55 gears. Would it get the same gas milage/power with 4.56 gears and 35's.

I know in the gear section it states, 35's/4.56 is close to factory 235/3.55. That being said, it most likely would not get same milage because of the extra weight and width of the 35's.

Well, now that I type it out, it seems I answered my own question.

Thanks for putting with my many thoughts of this never ending BKO love affair! It is getting expensive and tiring having to keep up two love's!:whiteflag
 

·
It's BTW Not AKA!
Joined
·
5,353 Posts
Doesnt it depend on the motor too ? you guys have 5.0 AND 351 ci motors-
Not really, they both came with the same factory gearing.
 
1 - 20 of 20 Posts
Top