Gear choices

[Ruffnek7tree]

In my 93, it has 4.10 gears to the best of my knowledge, and it's an n/A right now... plan to turbo it at some point, I have a factory kit

Main thing I'm gonna be doing with this truck is driving from north dakota to all over the PNW when I'm on my days off lol.. I might tow a car trailer with it on a rare occasion.. other than that, it's mainly just gonna be driven..

I have a sterling 10.25 with 3.55 gears, and I think it would be better for what I'm gonna be doing.. what kinda mileage can I expect both turbo and n/A? I plan on running either 265/75/16s or 285/75/16s on factory alloy wheels..

 

[Old Goat]

Do you have the ZF-5 speed manual or E4OD trans? They both have the over drive.
Your driving habits will be a factor.

I have an 86 6.9 NA, T-19 4-spd, 3:55 Diff. with 338K miles. UKN miles on IP or Injectors.
Tires are 235/85/16
I can get 20 MPG with summer fuel, and empty.
Hook up the 22 FT Boat Anchor (Car Trailer) and it drags it down a bunch. Load up a vehicle on it, drags it down some more.


Goat

 

[Nero]

There's a ton of hills here. My crew cab turboed has 4:10 axles and I average 15mpg unloaded. But I also hot foot it around a lot. I'd probably do better if I was a more conservative driver. Even with my 4:10 I can still hit 80mph.

 

[Ruffnek7tree]

I have a zf5.. being able to cruise without it sounding like it's gonna rattle apart would be nice lol.. which is why I'm heavily considering the 3.55s.. I want decent mileage and be able to cruise at highway speeds

 

[Black dawg]

3.55 will make it cruise nice with the zf5. First and reverse will feel a little bit tall with a load, but really nice unloaded.

 

[Austin86250]

I am always a 3:55 guy myself but if you tow more than you at empty go for 4:10

 

[Ruffnek7tree]

I am always a 3:55 guy myself but if you tow more than you at empty go for 4:10

What kind of milage do you get? Normally I cruise 70-80 anymore

 

[rreegg]

I usually drive pretty slow and keep it between 60-65mph and get about 18mpg freeway with 88 NA 4:10 unloaded - this is mixed hilly and flat areas of Hwy 5 through wa, or, and ca.
Turbo and 3:55s would be great for fuel economy and speed but I don’t sweat it

 

[u2slow]

I drove a 90 f250 idi extensively for a couple years. It was a ZF5 4wd and 3.54. stock size tires.

Great all purpose truck. Could rip on the highway, or haul whatever in a pinch (just pick the gear).

 

[Black dawg]

I recently went to 3.55 from 4.10 an a truck I have driven since 02. Unloaded mpg is way up even running 70 75 vs 65 before. Loaded mpg has been about the same, but also running about 10mph faster.

Ford did a lousy job gearing these trucks with the manuals with close ratios. Really could of used lower first and reverse, and a slightly better od ratio would have been nice.

 

[Ruffnek7tree]

Awesome guys! Pretty much confirmed what I was thinking... I'll be n/A for a while, probably later on this summer I'll swap it on..

What's everyone turning the ip up from stock and keeping decent milage? Isn't the recommended like one or 2 flats?

 

[Black dawg]

I really haven't found the fuel screw to have any effect on mpg. Been a long time since I messed with na, but 2 flats would seem like a lot to me.

 

[u2slow]

The 90 I drove belonged to a buddy. He had it turned up 2 if not 3 flats. It made more power for sure. Should have had a pyro but he didn't. Mpg change wasn't really noticeable (nor did we track it). I figure it's more about your right foot.

 

[Nero]

Even on a n/a if you're going to mess with the fuel screw, wouldn't be a bad idea to install a Pyro, long grades can still hit high egt's.

 

[Austin86250]

What kind of milage do you get? Normally I cruise 70-80 anymore

15 all day everyday cruising at 3k and risking coal everywhere, just installed a turbo so can’t wait to see what it will be now