The advantage of an Automatic Over Drive (AOD) transmission over the old C4/C6/FMX three-speeds are clear, you'll get lower engine rpms on the highway, therefore less engine wear, better fuel mileage, quieter cruising, higer top speed and a reasonable cruise RPM with 4.11 rear end.
Choosing the Transmission:
Retrofitting the AOD is a relatively easy "Bolt On" swap to any 289,302,351 engine blocks, the Bellhousing will fit like the old transmission.
Choosing the Transmission:
you will need of course an AOD transmission, you can use a used one from the late 85 and up to 93 cars that originally ware equipped with an AOD, but this is always a risk when you don't know if that old AOD has 1 more mile to go before it dies or 50,000 more mils of good service, one major guideline was in my mind when I had to choose a used part over a new\remanufactured part, The new, high cost part will eventually will be worthwhile cause it will last longer, though the used part is cheaper, usually it is only on the short term.
If you decided to go and buy a used AOD make, at least make sure it is an 88 aod or later, the 1987 AOD had poor lubrication to the planetary gears, that problem fixed by the factory in the 1988 and later transmissions with a revised output shaft that provided extra lube to the gear- train, and it will be safer going with the 1989 because some early 1988 transmissions still have the older style output shaft.
As a daily driver I wanted a 200% transmission, adding the fact I leave out side of the USA and AOD's are a rear thing in Israel, and shipping a bad AOD back to an ebay seller can cost more than the new one, I decieded to buy the TCI's AOD.
The remanufactured AOD's from companies such as TCI, Performance Automatic, Lentech Automatic, B&M Automotive, Monster Transmission & Performance etc... were built to be durable enough for the every day driver and they can take street abuse from the guys that will drive their car to the strip every weekend... from the TCI StreetFighter transmission I bought (part no. 431000) you'll get a Fully remanufactured AOD using only updated 1988 - 1993 cores, firmer than stock shifting, better over drive band, manual/automatic valve body and more, you can read more about that TCI's AOD here:
and here:
TCI Auto: AOD StreetFighterŽ Transmission
When I got my AOD I was so happy I slept with it in the garage...
Additional Parts:
To complete the swap you will need the following parts:
1. Flex Plate - There must be no mistakes whene you choosing flexplate, it MUST BE the correct flexplate or you will damage your engine, usually erly engines like the 289/302/ have a 28-ounce balance weight, while later engines like the 5.0 require a 50-ounce weight, on my 68 I have the late modle 5.0 so I needed the 50 oz Flex Plate, you need to make sure you know what is your harmonic balacer balance weight and the Flex Plate must be same! Another thing need to be consider when you are choosing a flex plate, the late-model AOD transmission requires a larger-diameter flexplate than the early C4 so you nee to find the proper one that will fit your application, because I have the late modle 5.0 (50 oz Flex Plate and 164 tooth) and AOD, I bought this flex plate:
B&M Flexplates: BMM-50238 - summitracing.com
Installed it on the engine:
2. Torque converter - You will have to use the AOD torque converter, it is always a good idea to use a new one, don't forget to fill the new torque converter with at least one, and preferably two, quarts of the correct-type Mercon fluid. If you forget to do this, you’ll have to take the whole job apart because the transmission won’t pump up. The TCI -432700 was my choice, it has a lockup to work with my TCI AOD, and it has a bit higher than stock stall speed for a little better lunches
TCI Saturday Night Special Torque Converters: TCI-432700 - summitracing.com
you will have a better idea on how to select a the right stall speed for you after reading this article
http://www.fordmuscle.com/archives/2000/09/converter/
3. Transmission Crossmember - you can not use your old transmission crossmember with the AOD, you'll have to buy it or fabricate it. I bought mine from Mustangs Plus for 139$ and it is comes with new mounting hardware, it is a nice piece made by Ron Morris
ron morris performance you can get it here:
Mustangs Plus*::*Drivetrain*::*Transmission Mounts*::*1967-70 RMP AOD Crossmember or any where you like.
4. Transmission Mount - You will have to use a C4 Mount, Don’t make the mistake of ordering an AOD mount because it won’t work! it is a good time to upgrade to a Polyurethane, it is Zinc plated and the Polyurethane is far more superior then rubber so it will do the job better and last much longer, I bought one from SummitRacing for 27$, definitely good investment -
Prothane Transmission Mounts: PTP-6-1605 - summitracing.com
Here you can see how the new Crossmember is mounted with no problems at all, just a direct bolt on, with the C4 mount on top of it. You might need to modify your exhaust down pips because the AOD's are wider than the c4's but it is depending on your exhaust system, I was going to the exhaust shop to redone all the exhaust system front to back right after I installed the AOD so I wasnt to worried.
This is after the new, Wider Exhaust:
5. Transmission Cooler - most of us alredy know that heat can kill an automatic transmission, TCI wrote a very clear "life expectancy" you can read it here:
TCI - TECHNICAL INFORMATION: Transmission Life Expectancy
In this case, Bigger is Better, so you need to choose the biggest Transmission Cooler you can install, I'm using the TCI-823800 (
TCI Performance Transmission Coolers: TCI-823800 - summitracing.com) in that chance I replaced the cooler lines to -6AN new lines, if you are not replacing the old lines, you should air blas tham to remove the old oil, you dont want the old dirty oil contaminating your new/used AOD and cooler.
The cooler should be mounted in a place that it will get a free flow of air and will not block the entire radiator.
If you want to be on the safe side, you should get a transmission Oil temp gauge like this one from auto meter
Auto Meter Ultra-Lite Analog Gauges: ATM-4457 - summitracing.com
I notice a healthy oil temp, between 150F to 180F, after I installed the TCI deep pan, the temp went down about 20F so it is running now 130F-160F, though it is not cheap IT IS ABSOLUTELY WORTH IT! with the deep aluminum pan the transmission can bear more abuse and will last longer, so 150$ will be a good investment.
The TCI deep pan holds 2 more qt. and has cooling fins to dissipate heat faster, it includes the proper filter, new rail bolts and washers, drain plug and pan gasket, no modifications are necessary to the dipstick.
TCI highly recommends to change the oil and filter after the first 500 miles, so a good idea will be (if you have a new transmission) to install the transmission with the stock pan, drive the 500 miles and then change the pan the filter and the oil, I did my first oil & filter change after my first 500 miles and than another oil and filter change after another 1,000 miles (total 1,500 miles) when I replaced my pan, "better safe than sorry"....
TCI Aluminum Transmission Pans: TCI-438000 - summitracing.com
6. Drive Shaft - Most AOD transmission is 1 inch longer than the C4, driveshaft must be shortened by the same amount. This is a good opportunity to replace those worn U-joints and if you can, consider a new aluminum drive shaft, this is definitely on my list. you can use the "Inland" website to do the measurement
Inland Empire Driveline Service, Inc. - Driveshafts, Pinion and Transmission Yokes, Center Support Bearings
7. Dipstick - Maintain the proper fluid level is important and sometimes even critical, to do it you will need the correct Dipstick, Lokare makes a nice piece that will be easy installation and also looks good, they have a flexible and not flexible dipstick, choose what ever you like.
Lokar Hi-Tech Flexible Braided Stainless Transmission Dipsticks: LOK-TD-3AODFM - summitracing.com
8. Shifter - you can use the original c4 shifter, you will have to buy or fabricate a linkage that will alow the old shifter to work with the the AOD like this one -
Mustangs Plus*::*Drivetrain*::*Automatic Shifter Parts*::*Performance Automatic AOD Shift Linkage
and you will have to make or buy the neutral safety/backup light harness, you can buy a complete one here:
Ron Morris Performance: AOD Neutral Safety Switch Harness
I think you'll better buy one of the after market shifters, you will have all the gears in the selector and you probably will not need the neutral safety/backup light harness because the after market shifters usually includs that, so it will be better, cheaper and easy to install.
I bought the TCI StreetFighter shifter
TCI StreetFighter Shifters: TCI-616443 - summitracing.com
It looks nice and not to flashy, it is reminding the classic one but more up-to-date.
As TCI say, "The shifter also feature a park/neutral safety switch along with a reverse light activation switch, 5 ft. of heavy-duty shift cables, and all of the hardware required for installation" are included so it is a complete package, it also has a "ratchet" mode to help you get a "no miss" shift, it is reminding the todays "tip-tronic" mode in the new cars.
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