my 85 f250 has the 6.9l diesel 4x4 and currently the 4speed manual transmission which sucks for the highway, is there ant other options for transmissions that will fit this application? i was thinking about going to an automatic but cant decide what would work better for me. i dont do any heavy pulling so the low low gearing isnt really needed

 

Your only option for a manual tranny would be the zf 5 speed. It has overdrive, but it has to come from a 7.3 diesel, since the zf has the bellhousing made into the tranny.

You could buy a overdrive unit and add to the rear of your tranny or the transfer case, but these are expensive.

Your only option for a automatic with overdrive is the E4OD. These usually need to be rebuilt with improved parts so they will hold up, and then you have to buy a computer system to run them, or get the factory computer system off a f250/350 from around 89-early 94 that had the diesel idi like yours and the E4OD tranny.

I put the zf in my 89, and am very happy with it. It gave me 3 more mpg on the highway, and it's much quieter with the lower rpms.

 

so a zf will bolt right in? any idea what the final drive ratio on the 4speed and the zf5speed are?

 

To add ...

The ZF must be from a Diesel 4x4 or F450.

And yes it will bolt right in with Ford parts, however you need to ensure you get the required parts to do the conversion.

4th gear in the 4spd is direct
5th gear in the ZF is .76

ZF S5-47
1) 5.72 5.08 4.14
2) 2.94 2.61 2.37
3) 1.61 1.53 1.42
4) 1.00 1.00 1.00
5) 0.76 0.77 0.77
R) 5.24 4.66 3.79

ZF S5-42
1) 4.65 5.72
2) 2.60 2.94
3) 1.53 1.61
4) 1.00 1.00
5) 0.77 0.76
R) 4.35 5.24

BW T18
1) 6.32
2) 3.09
3) 1.69
4) 1.0
R) 7.44

BW T19
1) 6.32 5.11 4.02
2) 3.09 3.03 2.41
3) 1.68 1.79 1.41
4) 1.00 1.00 1.00
R) 6.96

NP 435
1) 6.68 6.68
2) 3.34 3.34
3) 1.66 1.74
4) 1.00 1.00
R) 8.26 8.26

-Enjoy
fh : )_~

 

what are the different colums of numbers?
would i want ZF S5-47 or ZF S5-42?

 

The S47 has a better gear spand, it came out in the PowerStroke years, but will bolt up to an IDI.

 

will the 6speed zf from a 02 7.3l fit?

what parts would be required to do the conversion for a zf s47?

 

I am pretty sure the ZF6 will bolt right in!

No deference between in the S42-47, just the gearing inside.

 

If you find one for a good price, no matter what model number it is, you had better grab it.

The different number/ratio columns I believe are for gas versions or diesel versions. Looks like the 1st column is the diesel versions.

A 6 speed will not bolt in. It has a larger output shaft, so it requires the later model transfer case, and then you have no place to hook your speedo. And I believe the front clutch area requires modification to fit also, but I have forgotten all those changes required. Too much work for what you get, which is just a extra gear in the middle.

 

Columns are available gear packages ...

The difference between the S5-42 and S5-47 is input strength.
S5-42 = 420 (440) lbs torque. (580 / (600) Nm)
S5-47 = 470 lbs torque. (640 Nm)

Don't think the S5-47 provides any speedo hook up at all, where some models of the S5-42 do.

-Enjoy
fh : )_~

 

Speedo won't be a problem if you have 4wd and use one of the above zf's with a older transfer case that has the speedo hook-up. 2wd trannies for a 2wd truck would be a problem though, and the 6 speed is a problem since you have to use the late model transfer case.

 

the zf5 is good for a trans but a bit small for a 7.3 idi. mine is geared low, if i have to stop at a light, i make it to 4rth before get across and almost running red. top speed is 50 on 4:10.

what i need help with is figuring out transmission will fit this truck and the best option. needing at least 4 more gears and leaning towards finding a 13 speed. 18 would be a bit much. but i use this truck for work and travel over 10k miles a month and alot of times loaded or pulling. i get great mileage 20 plus if i can just make it to point b it would be nice. this engine is sound, just need some gears behind it to make it move and climb grades. its not uncommon to be finding 30 percent grades or better in my line of work. i dont care about firewalls, floor pans. i am already at 4.5 tons empty and 6 tons when loaded so the extra weight of trans is not a issue, plan on putting in 2 ton axles. also truck is 4 wheel drive so would like to keep that. i dont care about a different clutch setup as my firewall is already blown out and needing extensive repairs from metal fatigue. advice or directions on where to look or dig would be nice.

i know ford made a trans that was a 9 but could be made into a 13 that was in 4x4 medium duty applications for a 7.3idi. plenty of people talk about them but no one knows a name.

i know theres options but no one gives these trucks credit nor wants to talk about them.

 

You will find out a pickup is a pickup and it has it's limitations. Mainly the brakes. Some guys retro fit the medium duty stuff into a pickup(the 7.3idi is a medium duty engine really) but the pickup platform in my opinion is too small to do much serious hauling. And the highway cops are already wise, and are checking overloaded pickups and pickup based trucks on a regular basis.

You are correct, take the Ford bell adapter off, put the SAE adapter in its place, and you can run a heavier duty trans. They are large, heavy, and even noisier than the zf with no DMF flywheel, but you will get more gears. Your 4x4 may be a problem though unless you go to a divorced setup.