More questions on my 80 F350 DRW. It has a 400 (will have if I ever get it back from the machine shop), C6, 4.10 gearing, Hankook Dynapro AT2 235/85/16 31.6" tall tires. I have not driven it in this configuration but my guess is that it will be high reving at 60+ mph. What are the easiest and/or lower priced options for overdrive? Wont be towing a huge load or anything like that, maybe a smallish camp trailer someday.

EDIT - 1980 not 86. Past truck was 86 F250. Sorry for the confusion.

 

Now days everyone is use to the low RPM of over drive transmissions so when they start driving a non-over drive car or truck it SCREAMS!
Remember before over drive the RPM was normal for everything.

For the C6 transmission as far as I know you only have 1 to pick from and that is the Gear Vender over drive unit.
Sit down when you check the price they are not cheap.
You might get lucky and find a used one but also don't hold your breath.
Good luck and keep us posted
Dave ----

 

There are no cheap options, your cheapest options are a 5-speed manual or the E4OD Auto, and since the E4OD is an electronic shift trans so you will need a shift controller also. These options will be cheaper than an overdrive unit.

 

Thinking old school, wouldn't it be cheaper to get something like 3.90 or 3.73 gears ?

Is this going to be daily driver or just used when needed ? Just thinking cost virus benefit...

Do we know which read Diff you have ? Here's the page from my 86' owners manual. I gather you have 10 1/4" ring gear ?



https://www.drivetrain.com/parts-cat...d-pinion-gears

 

I have actually been looking in to a similar question for my LTD with an FE.

As others have said there's no real cheap option. I personally am considering a 4r70w swap with a controller. But for a truck application I'd probably snag a 6r80.

Here is an adapter for 351m/400 to a modular trans:
https://transmissionadapters.com/pro...5b3ce2a8&_ss=r
With a STEEP cost of 1675 for just the adapter... They also have a 351m/400 to chevy automatic for 875 I believe...

Then after that cost you get to buy a controller. For a 4r70w a us shift quick4 with all the added bits needed (tps, harness) you're looking at around 930-980 depending on the model year trans. (NOTE: a controller for a 6r80 will set you back even more)

So without even sourcing a trans we are at a very steep buy in imo...

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Instead of a 4R70 you could just use an AOD omit the controller and save yourself $900.

 

Definitely also a consideration. Then it's a matter of controller/4r70w vs aod +900$...

Edit: For me I'd need the adapter for either. Does the aod come with a 400 bell housing?

 

No, the only OD auto that came with the 400/460 bellhousing bolt pattern is the E4OD/4R100, and it also needs a controller.

 

Sorry, it's an 80 not 86. Dana 70 axle.

 

So you think a AOD would live in a 80 F350 DRW with a 400 motor?
I don't think I would go that route I would go with something a little stronger.
Besides you got issues with the rod adjustment and burning up the AOD trans.
Dave ----

 

It should be turning about 2700 rpm at 60 with those gears and tire size. 3.55's turn around 2250 at 60. As people are saying you have no real feasible OD options. Gear vendors overdrive is a nice unit but expensive. C6 is about as good as it gets for a 3 speed automatic and personally with how much money you'll have into a transmission swap that will buy a lot of gas. There probably won't be much if any MPG improvement with OD anyways. These old rigs turned high RPM's for hundreds of thousands of miles, for hours on end for decades with little to no complaints and it's nothing abnormal. I know what you mean about getting the engine back from the machine shop. Dropped a 352 off for boring and machine work 2 months ago for my galaxie and they still haven't started on it yet. That is frustrating!

 

A stock AOD from say a later 351 application or a 5.0L HO application or 4.6L behind a stock 400, the AOD would live quite happly behind it. You have to remember in this era the 400 was about 160 hp and about 275 ft-lbs of torque which is a fair bit less than the 180HP and 280 ft-lbs of the PI 351W and significantly less than the standard 210- HP and 260 ft-lbs of the early 4.6L used in the Town Car and the Crown Vic and the Grand Marqus that used the AOD. And then there is the 225HP 300 ft lbs of the 5.0L Stang that used the AOD.
So in short an AOD from the right application would live quite happy behind a late stock 400 in a F350 if it had adequate cooling and was not used in OD when loaded.

The AOD was put behind the H.O 5.0L, the SC 3.8 and all kinds of 351W and 4.6L powered Police Interceptor panthers. The AOD AODE 4R70W 4R75W are all the same basic transmission that share internal parts interchangeability (minus valve body) the only real difference is instead of a solenoid controlling the shifts in the electronic units it is a spool valve in the AOD

The TV adjustment is finicky to set but once done it's done. If the shifts start to drift or soften that is an indication of worn internal seals and time for a recondition. The AOD is one of few trans that has a built-in wear/condition indicator so to speak. The AOD was terrible in the beginning but by the end of production was an extremely reliable unit and could be built to take huge amounts of power(1200HP +). Once the issues with the AOD were resolved it was a very good unit.

 

Overdrive is great, and worth all the effort. I would get a E4OD for a 460. Should bolt right up. You will have to do some research on the flexplate, not sure what flexplate you would need to mate the 400 to the E4OD and it's torque converter. The controller is a fact of life with all the newer automatics. It does give you some neat features like the tow-haul modes like the newer trucks have. So off the top of my head, I figure you can get a rebuilt E4OD for $3000, the controller and wiring for $600-$700. You may need a driveshaft made or shortened, figure another $200 for that. You now have a highway hauler that can keep up with anyone on the interstate at 80 mph.

 

E4OD will use the same flexplate as the C6.

 

if your F-350 isn't 4x4, TC! has a 6-Speed Overdrive Transmission with interchangeable bell housings