1972 Mach 1 C6 to AOD to T5 Swap

[MKSpeedlab]

Well over the past few years, the Mach 1 seems to have gotten a new trans every year almost. The car is originally a C6 car, but a couple years ago I wanted to make some changes and make it a little better cruiser so I put in an AOD. The AOD was ok, but never seemed 100% despite having a Lentech VB and 3000 stall convertor. Well last year I took the car to get dyno tuned, and when the shop was adjusting things, they neglected to adjust the TV cable, so after getting the car home, I noticed the trans was acting up. After a very short period the trans was slipping and after talking with Lentech and some AOD people they figured the forward clutches are toast. Of course the shop is blaming everyone else and not taking any responsibility. So after fighting with them I decided Im just going to be done with the auto in the car and going to convert it to a manual. And I have to say I couldnt be happier. I went with a brand new Tremec T5Z and will try to share the journey with the pics I managed to get. But I have to say Modern Driveline had everything I needed, and I had pieced together a lot of other stuff to try and be as prepared as possible.
To prepare for things, I picked up another auto pedal support from West Coast Cougars, so I could prep it, get the clutch roller bearing kit installed and have everything ready. Little did I know the one I got through them was a little bit different, It worked, but had to make a few small modification.

The nice thing about the swap is most of the stuff is just Foxbody parts and everything bolts up nicely to the cleveland. I did have to clearance a couple small spots on the spacer plate, but everything went pretty smooth. I was very happy that we were able to remove the old AOD without removing the long tubes as that would have added a bunch of work. Went with a Ford racing billet flywheel and Mcleod clutch

One little sentimental thing I did was get my friends who were helping me to all put their initals in the form of inspection marks on the bell housing.

Pulled out the column to get room to work under the dash, plus it let me clean things up a little bit.

New pedal assembly in, wiring cleaned a bit. Looks right with 3 pedals finally.

Trans in, found out I needed a different crossmember so this was with the C6/AOD one, so I ended up ordering the Modern Driveline one.

The original starter ended up hitting the oil pan a little bit with the fox body bellhousing. So I ended up getting a new starter out of a 93 Mustang which was much smaller and lighter and works perfect. Just took a tiny bit of wiring for it but really simple and probably saved 10lbs.

Trans, driveshaft, and new crossmember in place. Everything looking/working good.

Ended up heating and bending the shifter arm back a bit to get a little more clearance. Used the Fox body lower shift boot to seal things. Clutch feels great and is just the MDL clutch cable kit, which I like because I can easily have a spare cable.

Lastly just a picture of the shift boot. My mom is a wizard with a sewing machine so she found some material and helped make one custom to fit the way I wanted it to. So really happy with how it turned out.

Now that its all done I have to say I am extremely happy with the swap. The car feels SOOOO much better and its much more fun to drive. This is probably one of the favorite things I have done to the car. I would have loved to have gotten a TKX, but it just wasnt in the budget, but I love taking the car for drives now as I had been missing having a manual. And even my dad had wished this car was a manual when he bought it.

 

[infopaivar]

Your article was very useful for me. I hope you will be successful. Thank you

 

[Sheriff41]

I've followed the same path - C6, AOD, T5 - and share your conclusions. The T5 handles the relatively stock 351C (mild cam, headers, intake, etc.) flawlessly. I'm running 3.91:1 gears. Cool idea with the initials!

 

[mrgmhale]

Bummer re: the Throttle Valve not being at a high enough PSI level to prevent frying the clutch pack. It is one of the things I e=fear after having replaced our 73 Mach 1's original C4 with and AOD the other year. I am not running 30-35 PWI, however. I wanted a little crisper upshift in 1-2, 2-3, and 3-4, and for those upshifts to occur at a higher road speed even n light throttle,. Moving the TV PSI to 39# did the trick. But not knowing if the PSI ever begins to drop, forr whatever reason, is driving me nuts. So, I ordered an LED oil pressure gauge that I will be plumbing into the Test Port of the AOD using a brass T sstand off. That way I can not only use that fitting to screw the pressure sensor into, but I can also very easily attach a mechanical test oil pressure gauge if I ever feel I want to. I plan to install the LED gaughe this month (July, 2024). I plan to video record the process, and post those steps, plus the end rersult, to my YouTube channel (Gilbert Hale), along with the 140+ other videos I uploaded - most of which cover some kind of diagnostic, repair, or upgrade routine on vintage Mustazngs and Shelbys.

Now that I have had the AOD for about 3 years in the Mach 1 I can I contineue to be very happy with the results. But, now that I have had to go through the revisions for the TV pressure from 35, to 37, to 37, and am about to instasll an oil pressure LED gauge to be able to minitor the PSI leverl, I wish I had held out for a 4R70W even it meant getting an aftermarket controller. Why? Because I could have made all the adjustments I made to the TV settings, and more, much more easily electronically via the controller unit. Live, learn, and share. I am in now hurry to have to replace the AOD. But, if that comes to pass, rather than rebuild the AOD I will get a 4R70W and an aftermarket electronic controller, and call it a day.