Pullin tha Trigger.....Maybe.....

[Bobby]

Hey guys! Need some guidance.
I, again, am 'seriously' considering converting my 72 Mach 1 to a 4 speed toploader from an auto. I've located a tranny and most of the conversion stuff. However, I have two parts that are proving problematic to find. I need a speedo cable or at least know if my current one will work or not. I have replaced all my gauges so I have an Autometer analog speedometer with a screw-in cable receptacle that I currently have plugged into the AOD. I also need to know if the current tranny support crossmember will work or do I need a specialized replacement. I've talked to NPD support and they have no answers. What say yall???

 

[Hemikiller]

A toploader uses a longer speedometer cable as it enters the transmission on the passenger side. With the screw on speedometer head, you may need a custom cable if you can't find an off the shelf part that'll work. The OE toploader cable was spec'd at 66 1/2" long. There are still companies that make custom speedometer cables.

https://speedometercablesusa.com/

The AOD uses a different crossmember than the toploader. A crossmember from a C4 or 3 speed car will work as well.

 

[Stanglover]

Drive shaft. Probably different too.
Clutch pedal bracket, you'll need to add bearings to support the pedal shaft. I used Mustang Steve's kit, but to be honest, I could have made my own bearing housings and bought bearings at the local bearing suppliers. I'd do that even if I had a replacement hanger bracket already set up for a clutch pedal.
Brake pedal will of course be different also, but you know that I'm sure.
What else................

 

[Bobby]

Drive shaft. Probably different too.
Clutch pedal bracket, you'll need to add bearings to support the pedal shaft. I used Mustang Steve's kit, but to be honest, I could have made my own bearing housings and bought bearings at the local bearing suppliers. I'd do that even if I had a replacement hanger bracket already set up for a clutch pedal.
Brake pedal will of course be different also, but you know that I'm sure.
What else................

I have already purchased a clutch/brake pedal assembly from a 71-73 donor car. I purchased it the first time I wanted to convert the tranny.

 

[Bobby]

A toploader uses a longer speedometer cable as it enters the transmission on the passenger side. With the screw on speedometer head, you may need a custom cable if you can't find an off the shelf part that'll work. The OE toploader cable was spec'd at 66 1/2" long. There are still companies that make custom speedometer cables.

https://speedometercablesusa.com/

The AOD uses a different crossmember than the toploader. A crossmember from a C4 or 3 speed car will work as well.

Thanks for the referral! I pulled up their website and have sent them message.

 

[Bobby]

A toploader uses a longer speedometer cable as it enters the transmission on the passenger side. With the screw on speedometer head, you may need a custom cable if you can't find an off the shelf part that'll work. The OE toploader cable was spec'd at 66 1/2" long. There are still companies that make custom speedometer cables.

https://speedometercablesusa.com/

The AOD uses a different crossmember than the toploader. A crossmember from a C4 or 3 speed car will work as well.

I found info that indicated that the C6 crossmember will work as well? What do you think?

 

[mrgmhale]

What a cool looking Mustang, and a very interesting project. I am more inclined to do automatic transmissions, likely because I have become spoiled over the years. On our 1973 Mach 1 we swapped out its original 3 speed automatic transmission for an Automatic OverDrive tranny. That really worked out well, the the OverDrive helped us recapture some fun top end performance, without sacrificing lower end performance. Best of both worlds. I recorded the entire transplant process on a series of YouTube recordings. I have two documents, each in two formats for a total of four files, available on my Google Drive that contain some useful AOD transplant info, and the YouTube video links. The link for the google Drive is:

https://drive.google.com/drive/folders/1-lnrDwhEKchMgNDYtRrIBkbNYjtrt3C9?usp=share_link

 

[Bobby]

What a cool looking Mustang, and a very interesting project. I am more inclined to do automatic transmissions, likely because I have become spoiled over the years. On our 1973 Mach 1 we swapped out its original 3 speed automatic transmission for an Automatic OverDrive tranny. That really worked out well, the the OverDrive helped us recapture some fun top end performance, without sacrificing lower end performance. Best of both worlds. I recorded the entire transplant process on a series of YouTube recordings. I have two documents, each in two formats for a total of four files, available on my Google Drive that contain some useful AOD transplant info, and the YouTube video links. The link for the google Drive is:

https://drive.google.com/drive/folders/1-lnrDwhEKchMgNDYtRrIBkbNYjtrt3C9?usp=share_link

Hi! I have an AOD that I installed last fall but its been a terrible journey filled with issues that delayed the install of the AOD. That delay, even though I had poured in the rebuilders prescribed amount of fluid in the event of storage. I had to have it rebuilt at great expense because of the 6 month delay in installation. My 383 stroker build went awry and delays seemed endless......so back to the tranny shop we go because it wont shift out of first gear. The toploader install will keep me with peace of mind and its also a built in anti theft device. Its also a great and fun experience to shift once again!!

 

[mrgmhale]

Hi! I have an AOD that I installed last fall but its been a terrible journey filled with issues that delayed the install of the AOD. That delay, even though I had poured in the rebuilders prescribed amount of fluid in the event of storage. I had to have it rebuilt at great expense because of the 6 month delay in installation. My 383 stroker build went awry and delays seemed endless......so back to the tranny shop we go because it wont shift out of first gear. The toploader install will keep me with peace of mind and its also a built in anti theft device. Its also a great and fun experience to shift once again!!

Drag. Sorry your AOD experience was not more akin to ours. That is not to say we did not have issues. All but one were very minor. In fact, one issue I "thought" I would have never was - I am actually using my original Auto Tranny shifter with the AOD. Yep, you read that correctly. If behaves a little different in the "1" and "2" positions on the shifter than with the original C4, but it turned out to be a good thing I left it in place as opposed to using an aftermarket shifter.

As for the worst thing that happened. The rebuilder, a national brand that will remain unnamed, used a solid pin for the shift shaft retaining pin. That pin is supposed to be an easy to remove rolled pin. Not a solid pin staked in deeply and that can't be removed. The reason I needed to remove that pin was so I could re-orient the Shift Shaft linkage arm, as they showed how to do in their own customer support videos. Well, because they used a solid pin and staked it in so deeply I could remove it, my project was in jeopardy. I ended up getting a carbide tipped hollow reamer to cut away at some of the aluminum case surrounding the solid pin they drive into the case, until I had enough of their pin exposed, Then I was able to grab it and pull it out.

Here is a video showing how we had cut into the case to remove the pin ("Shift Linkage Info Pin Removal"). The good parts are at cutting @ 06:40 mm:ss & Pin Installation @ 10:50 mm:ss

https://youtu.be/ank8xcr9ig4

The rebuilder did end up providing me some help for the added labor, and the cost of the hollow reamer I had to buy to fix the problem they caused.

I had considered a later AOD version, but did not want to have to deal with working with an electronic control unit to help it perform its shifting. There are some folks who make such aftermarket control units. I think that if I were to do the AOD swap again I might just get a later AODE or better yet a 4R70W tranny, and do all the adjustments from the controller. Those controller are costly, but rather than having to deal with adjusting the Throttle Pressure on the AOD I think that may have been a better choice. No regrets, our AOD is fine. But, if you end up finding it worth moving from your current AOD into something a bit easier to work with the 4R70W may be a good choice. Here is one of the site that offers control units for those transmissions:

https://www.usshift.com/usq4.shtml


If you do keep the AOD, which is still a fine choice, be sure to adjust the Throttle Valve Pressure or you will likely end up with a toasted tranny due to clutch pack failure. If you have not seen how to make that adjustment I have a few videos showing how I did it, did it again, and did it yet again. Why did I do it over? The first setting was to factory spec. But the 1-2 and 2-3 upshifts occurred earlier than I wanted, and I also wanted a firmer shift. So, I increased the Throttle Valve Pressure from 35 PSI to I think 37 PSI, and it helped. I later adjusted it to I think 39 PSI or so, which is where I left it. "Too much" pressure is not going to hurt the clutch packs. It is when the pressure is too low that you get into trouble. Here are my AOD Throttle Valve Pressure adjustment videos:

https://www.youtube.com/watch?v=8QncIKQTvNo


In this video I show how to connect the oil pressure gauge to the AOD test pressure port, and how to adjust the Throttle Pressure. In the video description I cover how to fabricate the AOD Throttle Valve Pressure adjusting gauge (0.275" thick). That adjusting gauge tool is critical to have. They can be purchased also, and in the YouTube description I provide the phone number and part # to order one. Also, in this video I show how the original shifter behaves with the AOD with detent positions, and gears, under different conditions.

https://www.youtube.com/watch?v=KYIAqqYUKNo


Finally, I have another ADO Throttle Valve Pressure setting video where I check what another person suggestged I verify. I had been setting my Throttle Valve Pressures in Park. The factory manual says to do it in Neutral. I was asked if Park and Neutral have different pressures, so I check and found that there4 is a slight difference in pressures in Park and Neutral. Not enough to get me into trouble, but enough to make note of it. Here is that link, which frankly I feel is well worth while watching, and reading the info in the description:

https://www.youtube.com/watch?v=6hZJEnGCPvY

 

[JJU9507]

Drag. Sorry your AOD experience was not more akin to ours. That is not to say we did not have issues. All but one were very minor. In fact, one issue I "thought" I would have never was - I am actually using my original Auto Tranny shifter with the AOD. Yep, you read that correctly. If behaves a little different in the "1" and "2" positions on the shifter than with the original C4, but it turned out to be a good thing I left it in place as opposed to using an aftermarket shifter.

As for the worst thing that happened. The rebuilder, a national brand that will remain unnamed, used a solid pin for the shift shaft retaining pin. That pin is supposed to be an easy to remove rolled pin. Not a solid pin staked in deeply and that can't be removed. The reason I needed to remove that pin was so I could re-orient the Shift Shaft linkage arm, as they showed how to do in their own customer support videos. Well, because they used a solid pin and staked it in so deeply I could remove it, my project was in jeopardy. I ended up getting a carbide tipped hollow reamer to cut away at some of the aluminum case surrounding the solid pin they drive into the case, until I had enough of their pin exposed, Then I was able to grab it and pull it out.

Here is a video showing how we had cut into the case to remove the pin ("Shift Linkage Info Pin Removal"). The good parts are at cutting @ 06:40 mm:ss & Pin Installation @ 10:50 mm:ss

https://youtu.be/ank8xcr9ig4

The rebuilder did end up providing me some help for the added labor, and the cost of the hollow reamer I had to buy to fix the problem they caused.

I had considered a later AOD version, but did not want to have to deal with working with an electronic control unit to help it perform its shifting. There are some folks who make such aftermarket control units. I think that if I were to do the AOD swap again I might just get a later AODE or better yet a 4R70W tranny, and do all the adjustments from the controller. Those controller are costly, but rather than having to deal with adjusting the Throttle Pressure on the AOD I think that may have been a better choice. No regrets, our AOD is fine. But, if you end up finding it worth moving from your current AOD into something a bit easier to work with the 4R70W may be a good choice. Here is one of the site that offers control units for those transmissions:

https://www.usshift.com/usq4.shtml


If you do keep the AOD, which is still a fine choice, be sure to adjust the Throttle Valve Pressure or you will likely end up with a toasted tranny due to clutch pack failure. If you have not seen how to make that adjustment I have a few videos showing how I did it, did it again, and did it yet again. Why did I do it over? The first setting was to factory spec. But the 1-2 and 2-3 upshifts occurred earlier than I wanted, and I also wanted a firmer shift. So, I increased the Throttle Valve Pressure from 35 PSI to I think 37 PSI, and it helped. I later adjusted it to I think 39 PSI or so, which is where I left it. "Too much" pressure is not going to hurt the clutch packs. It is when the pressure is too low that you get into trouble. Here are my AOD Throttle Valve Pressure adjustment videos:

https://www.youtube.com/watch?v=8QncIKQTvNo


In this video I show how to connect the oil pressure gauge to the AOD test pressure port, and how to adjust the Throttle Pressure. In the video description I cover how to fabricate the AOD Throttle Valve Pressure adjusting gauge (0.275" thick). That adjusting gauge tool is critical to have. They can be purchased also, and in the YouTube description I provide the phone number and part # to order one. Also, in this video I show how the original shifter behaves with the AOD with detent positions, and gears, under different conditions.

https://www.youtube.com/watch?v=KYIAqqYUKNo


Finally, I have another ADO Throttle Valve Pressure setting video where I check what another person suggestged I verify. I had been setting my Throttle Valve Pressures in Park. The factory manual says to do it in Neutral. I was asked if Park and Neutral have different pressures, so I check and found that there4 is a slight difference in pressures in Park and Neutral. Not enough to get me into trouble, but enough to make note of it. Here is that link, which frankly I feel is well worth while watching, and reading the info in the description:

https://www.youtube.com/watch?v=6hZJEnGCPvY

You are a very alive and helpful poster with awesome videos and pictures. You and your wife are a great team shown us how to work on those mustangs that is a beautiful orange color by the way I have been thinking about putting a 6R80 transmissions behind my big block But the controller and the adapter Val housing GS $2000 just for that why can I win the lottery !!

 

[HeavyCoupe]

You are a very alive and helpful poster with awesome videos and pictures. You and your wife are a great team shown us how to work on those mustangs that is a beautiful orange color by the way I have been thinking about putting a 6R80 transmissions behind my big block But the controller and the adapter Val housing GS $2000 just for that why can I win the lottery !!

100%. Learned some from his youtube vids before I saw his posts and put 2 and 2 together.

 

[bucketlist fastback]

I would love to see how your potential Toploader project goes. I have a 3.03 Ford three speed Toploader in my Mustang and would definitely consider a four speed swap like that.

 

[mjlan]

Maybe try finding a cable from a Ford truck?

https://www.npdlink.com/1948-1979-ford-truck/drivetrain/speedometer-cable-and-related

I would also poke around on Rockauto for different truck cables, some of the applications have pictures of the ends. They are in the 'Interior' section:

https://www.rockauto.com/en/moreinfo.php?pk=4223343&cc=1121465&pt=1440&jsn=1527

This application was for an 84 F-150

 

[Hemikiller]

I would love to see how your potential Toploader project goes. I have a 3.03 Ford three speed Toploader in my Mustang and would definitely consider a four speed swap like that.

The toploader is a direct bolt in replacement, as long as you get a correct style small block input, 28 spline output unit with the shifter in the right location. Luckily, that's the most common type made. The only "tricky" part is the speedo cable and gear.

 

[73GrandStang]

Out of curiosity, is there a reason why you're not going with a T5 instead? I believe the crossmember you have for the AOD would work, so that's one less thing to worry about...

For what it's worth, I converted my '65 from a C4 to a T5 and absolutely love it.