I know this question can go about 3 million different ways because of driving habits and mods, but I am going to ask anyway. Anyone have 4.10's in a two wheel drive? I was thinking 3.73's, but after some research I think maybe my 4.6 will do alright on gas with 4.10's. Thanks in advance.

 

What about 3.73, 3.90 or 4.30, mileage anyone? Or is it too bad, you just don't want to know? I hope this isn't the case. Stock I was getting about 19 to 21, with the 30 inch tires on I get about 16 to 17.

 

You may not want to get 4.30s with 30" tires. Granted the thing would have awesome low end power, but at 60mph you'd be running at least 2000 rpm. 4.10 gears would be enough to give decent power and not be hard on the gas.

As far as the other ratios go you can't get some of them. I'm not sure if you have the 8.8 or the 9.75, but given the year I'd venture a guess that its a 9.75. Regardless though the 3.90 gears aren't offered for it, or at least I haven't seen them. I know that you can get 3.55, 3.73, 4.11, 4.30 (don't know if thats available for the 9.75 or not but it is for the 8.8), and then 4.56. If you have the 8.8 you can go as deep as 4.86 and 5.13s.

 

he's got the 4.6 so he should have the 8.8" rearend. not really sure about gas mileage, but i would go with 4.10's for your truck. anything lower and your cruisingrpm's will be too high. good luck!

 

Not necessarilly. Some of the newer F150s with the 4.6L had 9.75s behind them.

 

Hey guys, thanks for the replies, but you misunderstood my second post. I meant anyone with 3.73, 3.90, or 4.30's in their truck to give me some ballpark figure for mileage. I am going to get 3.90's or 4.10's (and yes 3.90 is available for 8.8) I know WLF has 4.30's in his truck, I would like to know what his mileage is, he has a 4.6 also. But I am going to get gears installed within a week so I may have posted a little late. Oh well it is still interesting. Whatever I get I will post my mileage after a week or so if anyone is interested.

 

According to Ford the 3.73 gears will give you no loss of gas milage over the 3.55's, not sure about the others.

 

I made an appointment today with the gear man, and he doesn't carry the 3.90, so I am going 4.10. Those gears are gonna come in mighty handy this summer when I pull my boat! I hope to at least keep 17 mpg. Realistically I will probably get 15-16 at best though. Like I said previously, I will clue everyone in, if anyone is interested on mileage after the install.

 

My first tank I got 16.5, a little closer to my goal than I thought it would be. Especially since I have been racing quite a bit after the install. It has great power now, I can't wait to hook up to the boat this summer. I think 17 may be possible if I can keep my foot out of it.

 

Does the 4.10s make your truck wind up a lot on the highway? do you know a dramatic gear reduction? I'm thinking of the same swap for my truck with the 4.2 but I don't want it to be geared so low that the engine is always at its governor.

 

i have the 4:10 in the 4.2 and its to much gas milage is a poor 12.5 mpg changing in the spring to 3.73 also i have 35 in. tires

 

thanks road rage.

You think 3.73s with 32-33" tires will be good? I don't have any mods on the motor, and plan on only electric fans, exhaust and intake. You think my mileage will remain around 16-17? Did you do any other mods at the time when you swapped gears?

 

no but the tork range on the motor is very short meaning the engine winds up real fast rpms stay between 2200-3000 most of the time

 

RPM's are perfect if you ask me, but I have the 4.6. I run about 1900 at 60, 2200 at 70, if you are curious about 100 it right at 2900. After that i don't take my eyes off of the road long enough to look at the tach.

 

yes rpm is right for launching but for freeway driving it could be lower city mpg is 17 but highway is 12.5 and highway driving is what i do most.