Discuss 1965 Transmission swap from C4 to AOD on AllFordMustangs.com, the place for Mustang enthusiasts.
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Technical discussions specific to 1964-1967, 1968-1970, and 1971-1973 Classic Mustang. Discuss all tech related to in-line six cylinder and V8 powered Vintage Mustangs here.
I am anticipating changing my transmission from a C4 to an AOD. I have found a transmission shop that will do it, but they indicate that is is difficult and time consuming. I found instructions from I believe Mustang Plus that are very long and detailed and it does indeed look difficult. Am I crazy to do this?
If you are staying with a carburetor it is a lot more difficult than if you switch the engine to EFI. It may be worth looking into getting an EFI changeover at the same time as pretty much all of the parts should be available in a salvage yard except for the rear transmission crossover. You would also have to fab some mounts for the shifter cable.
If you are staying with a carb, the kit you refered to looks like the way to go. Pretty expensive though and if you have to hire all of the work rather than doing it yourself, I'm not sure it would be worth it.
If you are staying with a carburetor it is a lot more difficult than if you switch the engine to EFI. It may be worth looking into getting an EFI changeover at the same time as pretty much all of the parts should be available in a salvage yard except for the rear transmission crossover. You would also have to fab some mounts for the shifter cable.
If you are staying with a carb, the kit you refered to looks like the way to go. Pretty expensive though and if you have to hire all of the work rather than doing it yourself, I'm not sure it would be worth it.
not sure what the carb has to do with the transmission thinking of going from a c4 to an aod myself and was told there are alot of aftermarket parts available to make the swap relatively easy ( depending on your expertise, as well as some other factors). Seems to me the bellhousing is more import than the carb. Could be I"m wrong I haven't gotten that far with my car yet just touched on the subject while trying to decide on the engine
I am starting to dig through it - there is a lot of confusing misinformation out there -
For example - the MMM article says you have to shorten the drive shaft length, but a lot of people who have actually performed the swap maintain that you don't.
I have a guy here in town that owns a shop (has done a couple of swaps) and says he would do it for $700 labor. that is like 11 hours shop time here. I just need to find a transmission and the other parts (see article above) - I don't think it is that difficult.
Keep us posted - I will do the same.
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Beri Fraley Strong, Proud and Ugly
If you find yourself in a fair fight, you haven't been trained properly.
not sure what the carb has to do with the transmission thinking of going from a c4 to an aod myself and was told there are alot of aftermarket parts available to make the swap relatively easy ( depending on your expertise, as well as some other factors). Seems to me the bellhousing is more import than the carb. Could be I"m wrong I haven't gotten that far with my car yet just touched on the subject while trying to decide on the engine
Getting the TV linkage or cable to work right is the problem. If this is not done correctly it can cause transmission failure. If an EFI engine is used then all of the stock Mustang linkage can be used that is available at salvage yards as opposed to either buying the specialists kit or trying to get the linkage worked out yourself.
This forum won't allow a link to this site but if you google "Classic Mustang AOD Swap" the www. transmissioncenter. org page should be the first result returned. That page should be very helpful.
I was not saying it can't be done with a carb, just that all of the parts except for the rear crossover would be available at a salvage yard and thus considerably cheaper and will operate the TV cable correctly.
As far as the driveshaft goes, there are two different tailshaft extensions, a long and a short. I think with the short one the stock driveshaft will work. To check for sure insert the tranny yoke all the way in the transmission and it should need to be pulled back approximately 1 inch to connect to the rear end yoke. Much more than 1" will cause a vibration and less may cause a jolt to the transmission when a big bump is encountered which could cause major damage.
The reason some say you don't have to shorten your driveline is that there are two lengths of AOD. The long tail shaft version requires a shorter driveline but it can also be the weaker of the two. The best way to build an AOD is to swap the internal parts from a 4R70W into the AOD and get an after-market valve body for the AOD.
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1966 Coupe 351W Top Loader rebuilt, rewired, modified for slalom and hill climb No racing - just a fun car built by and for me. Project in process
I just completed the C4 / AOD swap, and although not complicated, you will run into some obstacles. I personally think the swap was worth it, because now I can run my car at highway speed and have the engine loaf along at 2000 rpm or so instead of 4000 rpm. I'm running a 3.55:1 gear in the rear end.
I am an amateur at best, and I've found that if I take things slowly and deliberately, I'll do OK. Saying that, I did have some obstacles that I ran into. Most are well-documented, some are not. Here's what I've learned:
1) Driveshaft shortening. As others have pointed out, you may or may not have to have your driveshaft shortened. My advice would be to get the driveshaft from a car equipped with an AOD and remove the yoke. Use that yoke to mount up to your existing driveshaft. Measure the required driveshaft length and then see if you need to have your driveshaft shortened. Yes, you can use the C4 yoke, but take it from someone who had to have the shaft worked on twice, get the AOD yoke, measure the required length, and then go to the driveshaft shop to have whatever you need done.
2) Exhaust. I am running Tri-Y headers with dual exhausts, and I had to have the flanges on the pipes moved away from the transmission case. Both pipes were hitting the case and I had to have some work done to move them around. The AOD's case is larger than the C4's.
3) Emergency brake. Because the transmission mount is further back towards the rear of the car, the connecting point for the emergency brake cable is also closer to the rear of the car. That means the two cables going to your rear brakes will now have some slack, that may or may not be taken up when you adjust the cable.
4) Flexplate / Torque converter. Be VERY CAREFUL here, and make sure that you have the correct flexplate for your setup. I didn't, and when I mated the torque converter to the flexplate and subsequently joined the transmission to the engine block, I smashed the transmission's pump and trashed the torque converter. You need to make sure the mating surface of the flexplate is the right distance from the mating surface.
I am happy to call anyone that's contemplating the swap to discuss this. Just send me a PM with your phone number.
66 coupe EFI/AOD swap here. I used the original C4 yoke and shortened it by 1 inch. Took it to a machine shop, they cut off the one inch. I used my grinder to take off some sharp edges. I didn't do anything at all to the driveshaft from my 66 C4, just put it back in. As far as the TV cable is concerned, Lokar makes a cable that you can use with a carb/AOD. I bought that, but I thought it looked kind of flimsy, but that's just me. I went with the Ford TV cable from a Mercury since that's where my AOD came from. I set the tension myself and have had no problems at all, 2 years and counting, at least 3K miles. This swap can be done by a 'backyard mechanic' if he has good skills. I think $700 is a lot of $ for this swap. It can be time consuming, but very do-able. PM me if you need to.
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1966 Mustang, Wimbleton White 5.0L EFI/AOD
1963 Thunderbird
Ancient Ford lawn tractor
Currently on my 5th Mustang
1965 Transmission swap from C4 to AOD 
thinking of going from a c4 to an aod myself and was told there are alot of aftermarket parts available to make the swap relatively easy ( depending on your expertise, as well as some other factors). Seems to me the bellhousing is more import than the carb. Could be I"m wrong I haven't gotten that far with my car yet just touched on the subject while trying to decide on the engine
