Guys:

I am still knee deep on my 1966 F250 4X4 restoration / conversion. I just completed overhauling the brake system and looking at drivetrain now. I am going to put in a newly overhauled 460 engine with a C6 transmission with a Hughes fuel miser torque converter and US Gear overdrive. This combo has pretty much been bullet proof in my 1966 F250 2WD. I was considering looking at a 2WD E4OD instead and putting my US Gear overdrive on it but was unsure if it would be too long to work with my divorced Dana 20 transfer case. I was also unsure how the E4OD would hold up in towing situations. I have purchased a Dana 61 with 3.07 gears and also 3.07 gears for the front Dana 44. I'm going to have the Dana 61 narrowed to fit under my 1966 F250 frame. I know the C6 can handle the extra towing stress of the higher gears as I have been running 3.54 gears in the 2WD but not sure about the E4OD. The 460 has so much low end torque it really runs well with the higher gears also. Basically I want the best possible fuel mileage and drivability on the highway and will use the 4 low range in the transfer case to work on my farm. Any information and suggestions would sure be appreciated. This board has sure been a great source of information over the years and has sure saved me a lot of time and effort during my 2WD restoration / conversion and now my 4WD. Thanks guys!

 

Yes. An E40D is around 6 inches longer than a C6 that's gonna be too long with an overdrive. Not sure why you would put an additional overdrive on an E4OD anyway??? A properly built E4OD will run at least $2,000 with converter and should hold up to anything you can throw at it. I would do either or. I'd run what you have since you already have it, and the E4OD will need a computer control system to run it.

 

Do you think the C6 with the US Gear overdrive will fit in the 4X4 without moving the transfer case back? Thanks!

 

One of my 66 F250 4x4s still has its 352 FE and NP435 4 speed. From the output of the NP435 to the transfer case is only about 6 inches of working room if you had two yokes welded back to back (not recommending that) so without moving the transfer case back or the engine foreward there is not a huge amount of extra room. The C6 is longer than the NP435, I think. Add in an overdrive on the back of the C6 and it could get a bit crowded between the two. If you move the transfer case then you've got 3 driveshafts to shorten or lengthen or get made up custom.

I was going to put a Gear Vendors on the back of the NP435 but it needs about 12 inches and there just isn't that much room without moving TC back a few inches. About the same story for Ranger overdrive. It mounts in front of transmission so everything gets pushed back.

You might be able to put the 460 forward a bit since you have to use custom engine mounts anyway, I imagine.

The 120" wheelbase just doesn't give a lot of options. I'll be interested in what you decide to do.

 

I definitely have some concerns about my C6 fitting between the engine and transfer case now. Even in my 2WD there isn't a lot of space left with the C6 and overdrive unit and 460 engine. On the 4X4 it will be even tighter. Thanks for the information! Definitely will save me some time and expense. Send me some pictures of your 1966 F250 4x4. Would love to see them.