I have a 93 f-250 with a 460 i am not good with this gear thing but i don't use my truck to tow anything really heavy maybe the most weight i would tow is three 4wheelers but most of my time is is city driving i wanted to know what gears would be best for my truck i want mpg but still power. How much mpg can i gain with changing gears an is it really worth my money for the gears? What gears? I also have a e40d transmission.

 

4:10's should work for what your wanting.

 

Yea i have 4:10's now there is nothing better then those?

 

With the info above can anyone tell me the pros an cons of the fallowing gears.

3.90
3.73

 

I'll bet you could drop down to 3:55 with no problem, I have them in my 86 F350.

 

I was thinking 3:55 do you notice any difference in mpg or did it have 4:11 or 4:10'?

 

Jeremy, my truck came with them. I bought it used in 1995 to tow my 5th wheel trailer. It used to get 10 to maybe 10.5 mpg empty and 8 to 8.5 towing. The combination weighs 16,120 lbs. I am going to be changing from a C6 and carburetor to an E4OD and EFI fairly soon so I will see what that does for fuel economy. My previous truck would get 16-17 mpg solo with a 390 4V and 3:25 gears.

 

With an F250, gear swapping is going to be a bit tougher. The highest gears available are 3.54, and they ain't cheap:

Dana 60 Differential Parts Ring Gear & Pinions, Positraction - Drivetrain.com

You have 4.10s and an E4OD with a .71 4th.


What size tire are you running?

A 285/75 x 16 is 33 inches tall.

With that tire, you should be running about 1926 rpm at 65 mph.

With a 35 inch tire, it drops to 1816.

Change to 3.54s and with the 33s you get 1663 and 35s you get 1568. You might get some hunting with that set up and a load and a hill.

Since you say most of your driving is city, I don't see how even a taller tire would pay you back, as the only gains to be made with taller gears for you would come from long trips at modest speeds unloaded over flat ground....

 

Wouldn't a 93 still have the Ford/Sterling 10.25" rear? I have three of those in my possesion at present. The dually rear in the truck, 3:55 open, another dually rear from a 92 or 93, 4:10 open and a single rear wheel from a 90 F250, 3:55 limited slip. I plan on putting the 3:55 limited slip in the later dually housing since my housing has a bad left tube where it spun a bearing in 2000.

 

Thanks for the correction.

However, regardless of axle type, the point is, a ratio change isn't going to make much of a difference for mostly city driving, and the 4.10s are probably better suited to that kind of driving. ymmv.

 

ok so i have 33" an 4:11 i am not sure what rear end i have but going to 3:55 would not help my in town mpg?

 

Does your trans shift into OD in town? At 35mph with your set up, in OD you would run 1040 rpm. It probably won't pull that, so it goes to 3rd and runs 1464.

With 3.55s, it would run 898 rpm at 35, but won't pull that, so it would go to 3rd, running 1265. Might pull that, might not. If it goes to 2nd, now you're at 1948 rpms, and it will shift back and forth between 2nd and 3rd.

City mileage will depend mostly on your right foot methinks, regardless of gearing.

 

You won't like the 3.54 or what ever is close to that, no power. I'd go 3.73's you will like those. They will still have some power coming out of the hole and the overdrive will still get you some mileage.

 

Mark, why would 3:54, or 3:55 not have any power? My 86 has a ton of power with 3:55 rear, it will actually light all 4 rear tires if you stomp it. I towed a 30ft 5th wheel with it for a number of years with no problems at all. It climbed 7 mountains grade on rt. 322 in Pa. at 37 mph in 2nd gear.

 

I kinda agree with you labaron. Only I travel 322 regularly and I wouldn't call them mountains. Lol. City driving is mostly how you use the skinny peddel.

The expence of gears isn't realy worth the reward. You would need to make a drastic change for a purpouse built rig to make it worth it. 4:10-4:11s are a good all purpous ratio