AOD Swap

[jason barker]

I want to put in a aod tranny what all do I need to buy?

 

[70_Steve]

http://classicbroncos.com/tech/aod-3-speed-automatic-transmission-guide

 

[Viperwolf1]

Depends on what tcase you plan to use. For D20 you'll need the AA AOD adapter or you can use the ZF adapter if it's a 4wd AOD. There may be tcase shifter issues with the ZF adapter. You'll need to modify the cross member and move it back. You'll need to shorten the rear driveshaft and lengthen the front. Then there's the gear ratio problem. AOD has a .67 OD gear. You'll need to go deeper in the axle gears to make the trans happy. How deep they need to be depends on tire size and engine torque. With a 302 and small 33's I'd recommend at least 4.88 gears.

 

[Broncobowsher]

While you are researching it out, also look at the 4R70W. It is a vastly updated transmission that replaced the AOD. It installs nearly the same.

Using the AA adaptor either transmission will need a rebuild to install the supplied output shaft.
Finding a 4WD donor you can skip the rebuild and use the AF to D20 adaptor, but more crossmember work is needed.
Or the cheat way is to find a Ford NP205 and with a little notch in the factory 4WD adaptor it will bolt up. But there were a few different versions of yoke configurations of the NP205. And low range is a lot worse. And it is big and heavy. But it does just barely fit inside the frame rails (unlike any modern chain drive transfer case).
Or the high budget version of getting an Atlas or a Stak aftermarket transfer case.

All variations will require reworked or replaced driveshafts.

Short list of other stuff.
Starter (auto trans starter has a different nose cone then the stick)
Flexplate (need to match the balance of the engine and correct offset (C4, AOD, 4R70W (not C6 or E4OD)), tooth count (164 is the only tooth count used on the AOD/4R70W), torque convertor bolt circle (11.4"))
Torque convertor (if not included with the trans, must match the trans. AOD only works in AOD, C4 only works in C4, 4R70W only works in 4R70W)
Some sort of cooling and lines
Some sort of shifter
Crossmember

Probably a few other little bits just to get it in and running

then to use it, you need low axle gears. 4.88 gears in overdrive are like a set of regular 3.25 gears. So overdrive will be useless with a set of 3.50 gears, and if you are running factory 4.11 you will pretty much need stock height tires to have a chance of running in overdrive.

 

[jason barker]

Wow, thanks for help!

 

[hyghlndr]

I have a used AA adapter for the AOD to D20 if you are interested.

 

[igottastanger]

I have a used AA adapter for the AOD to D20 if you are interested.

How much do you want for the adapter? Is it the kit or just adapter plate to mount the d20 to aod?

 

[BUCKNBRONK]

Make sure the kit has the output shaft, rear tail housing, bearing cone with output support bearing, also a oring that goes on the cone and gasket for the tail housing. u cant just mount the d20 to the aod the trans has to be disassembled and the the new output installed. While ur there new clutches and drums and a few update parts are advised. The donor aod should be a 1988 or newer for better oiling and u have the choice of manual or electric od valve bodies. TV cable is very important to set correctly on these trans. Its not a cheep upgrade but I love mine.

 

[360 4V]

The AOD is convenient if you are running a carburator and don't want to deal with a computer to control your transmissions electronic functions. The AOD has problems. I upgraded the following:
300M 1-peice input shaft
C6 torque converter
AODE/4R70 intermediate clutch pack
.345" thick pressure plate for the low-reverse clutch pack with three standard thickness frictions and two steels and a .064" thick snap ring
I set the forward clutch up with six frictions and steels, no wave plate, a .195" pressure plate and a .064" thick snap ring

The Direct clutch pack got six frictions, six steels, a .123" thick pressure plate and a .054" thick snap ring.

The intermediate clutch got 4 frictions, four steels and a .258" thick pressure plate. Standard 4R70 V8 parts.

With the AOD you get three forward gear selections, 1,3 and overdrive. You can perform the epoxy mod to have 1,2 and Overdrive. This is why I am saving up for a Silverfox valve body with overdrive delete. Just a heads up.

If you are going EFI anyway why not get the engine and transmission together to save a lot of trouble. The AODE has a stronger input shaft design and has electronic overdrive delete. The AOD makes a great transmission but you have to build it up.