I have a 66 F100 4x4 with a 390/4spd. "granny" trans/Dana 21 transfer case. I sourced a 5.0/AOD(non computer)/trans case from a 86 Bronco and considered a swap. I am unsure if the motor will bolt up to the existing motor mounts. Anyone performed a swap like this?

I also thought about purchasing a kit (expensive), that will bolt the 390 to the AOD/trans case from the Bronco, giving me a needed overdrive for the 390. Does anyone know of an overdrive manual trans?

Currently, the 390 is a gas hog and unsure if the AOD swap will make it better. I am also unsure if the 5.0 will have the needed power for the rig, while I am sure it could get better mileage. I have even considered a diesel engine. Lot's of options.

The rig will be for my son to drive to high school. Like I said, anyone have any experience on what engines perform better in these light trucks?

Many thanks!

 

buck, Unless someone has swapped the 390 in, your truck has a 352. The 66 4X4 is on the 61-64 chassis with front engine mount, so mounts for the 302 would have to be fabricated.


Believe you would be lite years ahead to buy the a cheep car to drive to school.


John

 

The 66 4x4 has the front suspension with coil springs and radius arms, how could that be the same frame as the 61-64 that used leaf springs?

In stock form the AOD would never hold up to the power and torque from a 390 and I would not even try to go down that road.

Jeff

 

Sorry John, But in this crumbling world we should be allowed to do what we wish.
This will teach his son responsibility and how to ration gas, thats what my rig did for me in high school.

Well Buck, he is right, unless you or a po have put in the 390 it is a 352. I prefer it cause it has more power than most people need. Check out the FE forum for more detail on the motor, as I have seen the debate for the best transmission never won. But I prefer the older 4 speeds such as the T-18 or Np435 like what you have. You can get a gear splitter from gear vendors but thats pricey.

As for the 302 (5.0L), I have heard that the motor perches up to 72 will fit with a few extra holes drilled. A 302 when built right will power your rig no prob, and its a swap I have seen done a few times. More will have info on this site, don't worry I've seen many questions answered including my own.

And most of all, Welcome to FTE!!!

 

I think looking to an engine/trans swap to solve your fuel mileage issue is a waste of time, effort and money. Don't you just love internet opinions?
Your problem is multi-fold: the gearing in the differentials, the weight, the barn-like aerodynamics and quite possibly your right foot. An FE (352 anyway) can return 15 mpg in a F100 2wd truck but I'd say it's highly unlikely in a 4x4 (or an F250). That's due to the gearing. While an aod may help gain you a few mpg I think we're talking low single digits. Only you can answer if the investment is worth it.

A small block engine IMO will have to work harder and turn more rpm's than a big block that specializes in torque. If it really is a 390 you're going to miss that bottom end power. 302's are great fun in Mustangs but I don't think they make great truck engines. Probably the reason Ford didn't do it for a long time.

I agree with another poster...if getting some better mpg is the goal, the world is full of sub-$1000 Escorts just waiting to return 30+ mpg.

 

FWIW- I have a 4X4 250 W/ 433 gears (i think) in it and i get almost 16 mpg with it. problem is i very seldom hit 60 mph with the truck. i hook my 5th wheel camper on the back and travel around the 55 mph speed and get 14 mpg with it. the 300 six in it has all the power i'll ever need. but if you're one of those people that has to be somewhere right now it's prolly not an option. jsut my opinion. i really like the truck. Dutch

 

To use a 302 you need specific 302/351M400 mounts for a four wheel drive application, The mounts from a later truck up to 1979 is what you need. A 302 will not fit correctly on the FE/I6 Mounts.

The 66 F100 is the only oddball of the four wheel drives in the 61 to 66 series. The remainder use the early 59 type ladder frame and setup.

You can change out the front and rear gear sets for better MPGs, just remember to match the sets in ratio.


Garbz

 

John, the66 F100 4x4 uses the side engine mounts and not the same as the 61-64 frame. But the frame is Not like the 66 2wd frames.

 

I knew I shouldn't use my recall for something I don't know much about.

Sorry guys.



John

 

WOW! Thanks for the help! I guess I should have included more information. The 390 is out of a '73 F250, that's why it probably bolted right up like a 352. The truck was restored by my dad several years ago and is a sharp looking rig, ie: rally wheels, custom interior, hard bed cover, etc. He talked about giving to my son...lucky stiff, but wanted a better engine/trans option, as it most definately needs an overdrive. I have seen some sites that have an adapter for an NV4500 transmission, if I could find one, and I would have to use the transfer case from the Bronco I parted out. The kit, which I think was about $700 left me with still using the stock clutch linkage too. That may be the way to go...the 390, with an NV4500.

I agree, the 390 power would be great, as the one in there was taken from a salvage rig and is in need of a rebuild and pretty tired, not to mention a real gas PIG.

I have thought about a Gear Vendors unit, but they are WAAAAY to proud of them to spend on a kids rig! HAHA!

If none of this will work, maybe I can sell the drivetrain from the Bronco! Any thoughts?

 

I'd send a photo if I could figure out how!

 

Rebuild the FE for max fuel economy and let him manage the fuel rationing and be done with it. 1500.00 should be plenty to get that done IMO.

 

I like that option the best...the cheapest! Do you know if any of the newer 5 speeds will work with a 390?

Just checking.....

Sounds like what I have may be the best option! It will teach him a to have a light foot.

 

When I went from the 352 to a 390 in my 66 4x4, the MPG went up. The engine works less, better wieght to hp ratio. I have squessed 15-17mpg out of it.

 

My conversion from a 3-speed to an AOD caused a net loss of MPG. I believe it is because of additional effort to drive the pump, additional weight of the tranny, and running at a lower RPM that is less suited for the 302. It did however, reduce engine noise, left leg clutch fatigue, and it freed-up the cell-phone hand! Oh, the previous posts are right about torque. Way less than the 352 in stock dress.