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Ford’s Automatic Overdrive (AOD) was firstly used in 1980 before it became an overly electronic controlled transmission AOD-E in 1991. There are simple, yet effective ways to modify your ford AOD transmission to perfection and that is what this blog post is covering.

Prior to commencing your Ford AOD transmission modifying project, it’s necessary you have an ideal work setting and most importantly, the required tools for the job all available. 

Since automatic overdrive transmissions entail several tiny precision parts like clips, valves, balls, springs, pins, and the likes, your workshop environment should be in order, neat, and well lit.

It is possible to modify your Ford AOD transmission perfectly by replacing some of its core internal components using aftermarket kits. Envision the Ford vintage AOD as a core component that needs to be replaced with the perfect parts to boost its performance.

Like Trudi Dufek’s 1963 Ford Falcon Sprint modification, modifying your vintage car means taking it to another level, and such is like the ace of spade to win a lady’s heart. Of course, we are going to show you how to make your AOD better.

Now, do consider the following points on how to modify your Ford AOD transmission to perfection:

1. Use the Perfect Aftermarket Parts

Selecting and using the right aftermarket parts will determine the kind of performance you get after modifying your Ford AOD transmission. The wider AOD overdrive band and reverse drum will take the load better.

When done right, the transmission should be able to take 800-1200 horsepower (hp) in some cases which overset or translate into a rugged and dependable AOD. You can also take it a step further should you go for the 4R70W. It has the ability to increase car acceleration as a result of its better gearing. 

In the same vein, the 4340 chrome-moly durable input shaft should be used too since it can deal with the input shaft breakage puzzle glaring in stock shafts. Consider the “A” Overdrive servo too to achieve the clamping pressure of the greater Overdrive band.

2. Adjust the Throttle Valve Cable

Modifying your Ford AOD into perfection also requires you to adjust the throttle valve cable. Hence, it’s very crucial you note that the throttle valve (TV) cable can be adjusted in two different ways.

One involves using the pressure gauge, and the other is doing away with it. However, you should make use of the pressure gauge by screwing it into the pressure port line which is located at the right side of the AOD transmission case.

Similarly, with a pressure gauge already screwed into the pressure port, you should see 0-5 per square inch (psi) at idle speed and 30 pounds’ psi per normal acceleration. 

At wide-open throttle, you should at least see 85 pounds’ psi of the line pressure. Thus, if the speed is idle, there will be a slack tension on the TV cable, meaning there should be no tension and no slack either.

Equally, if you will go for the other available option i.e. adjusting the TV cable without the pressure gauge during the installation process, the cable tension should not be slack also.

Be that as it may, applying the gear shifter should bring a gentle engagement result in place of a jolt. At this point, a test drive is very necessary starting with a soft acceleration and then after, a hard acceleration.

A light acceleration should produce a firm upshift time with a speed increase while a hard acceleration should deliver a delay but quite firm shifts. In case there is slippage, the cable tension should be increased. 

That is to say, under no circumstances should there be slippage. If there is any, the cable tension should be increased, or else, the transmission will overheat and burn.

3. Torque Converter Proper Installation

When it comes to Ford AOD modification, special care is needed for the torque converter installation because nothing stings AOD installers more than inappropriate torque converter installation.

Therefore, make sure that the torque converter is properly installed on both the basic and secondary shafts, front pump rotor and stator support to prevent front pump failure or damage. 

Also, make sure that there exist three moments that will enhance the converter to conveniently pop to the next rank. You will know if the converter has been placed into its right position the moment your hand can’t pass through the bell-housing and the converter.

4. Use AOD Adaptor and Conversion Kits

In the process of modifying Ford AOD transmission to perfection, torque converter installation and adjustment looks straightforward, when an orderly and methodical approach was used to ensure success.

However, with an AOD adaptor and conversion kit, you will be able to freely install an AOD in almost any vintage Mustang too, excluding the 200ci and 170ci inline-sixes.

Specifically, the California mustang AOD conversion kit doesn’t have an AOD adaptor. However, it does have a trans mount, flexplate, cross-member, throttle valve cable, ‘65’- ‘66’ parking brake bracket, slip yoke, adjustable manual shift linkage plus installation hardware.

Lastly, these kits will aid you to get overdrive mounted in your car efficiently in no time making your work lots easier with more productive results.


If you can commit your heart to it, you can build a perfect AOD transmission today. It all starts with making a choice between the 4R70W or AOD-E as your AOD core. You will also have to carefully pick the perfect internal components. After all, they will contribute immensely to the performance level of your Ford Falcon machine.

To round things up, the above-explained are simple but effective ways you need to master how to modify your Ford AOD transmission to perfection via the use of aftermarket kits and off-the-shelf components. 

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