I couldn't find exactly what i was looking for so excuse my ignorance if this same question has been answered as i was unable to find it.

1978 302 with no mods other than basically an rv cam. Gives a little more torque changed my firing order to that of a 351 or 302 HO. Being a 78 and in CALIFORNIA its bogged down with all that smog BS.

I have a c6 going to i believe a Dana 60 with gears at someplace from 3.00 to 3.25. Not sure exactly.

If and when i finally do upgrade that 302 i will be keeping it small block and not exceeding 300 hp.

So the question is...

Should i replace that C6 with a C4 or an AOD.

This is a cruiser doesnt do any work other than the occasional full bed helping a friend move.

I do know the C4 consumes less power than the C6 to operate but im not sure how efficient the AOD is. And i know the AOD has that 4th gear. So better mileage from either one over the c6 not sure how much compared to each other though...

Would a c4 or aod make more sence here? And finally if its a close call considering my application here, would one of these be considerably easier or more difficult swap for the c6?

Excuse the long post wanted to make sure anybody who may answer had as much info as needed.

 

I would say if there is nothing wrong with the C6, leave it in. But that's just my personal reference...

 

Well im thinking i would be able to free up quite a bit of power and improve mpg in the process since the engine isnt working as hard. I have heard abt. 60hp from c6 to c4? not sure how accurate that is or isnt though.

 

No way it would free up 60hp. There is quite a bit of difference going from auto to manual though. I cant see the sense going from a c6 to c4. AOD on the other hand....

Guess it comes down to how badly you want overdrive.

 

AOD actually wouldnt work out so well id have to change the rear since im only running about 3.10s or so...

A guy on here said this and everybody seemed to agree at least nobody went against it. So thats what i was going by...

Transmission Hp Consumption
Originally Posted by stuart1
Powerglide_____18 hp
TH-350________36 hp
TH-400________44 hp
Ford_C-6______55-60 hp
Ford_C-4______28 hp
Ford_FMX______25 hp
Chrysler_A904__25 hp

 

Can you explain what you mean by this?

I have a 289 with the HO firing order, 5.0 efi, AOD, and 3.00 gears and she runs just fine. Fun around town and 70 MPH on the highway.

Mark

 

I would keep the 3:10 gears with overdrive. The 60 hp lose with a c/6 i do not believe. It sounds like you are trying to go both ways,more h.p. to get up and go and economy. They normally don't go hand in hand with these old trucks.

 

Transmission Hp Consumption
Originally Posted by stuart1
Powerglide_____18 hp
TH-350________36 hp
TH-400________44 hp
Ford_C-6______55-60 hp
Ford_C-4______28 hp
Ford_FMX______25 hp
Chrysler_A904__25 hp[/QUOTE]

If this chart is right you wouldn't gain 60hp switching to a c-4 anyways. You would only gain 32 to 37 hp however I don't think you would. I would stick with the c-6 but If you want to spend your money and time then go with the aod. Just my .02

 

I know i wouldnt be gaining all that power lost due to the new trans still using up some of the hp, just not as much. I wasnt thinking of ramping up hp and mpg with this. I thought i might see some improvements in both areas, neither being drastic. If anything more mpg would be better anyhow to me. Just thinking it would be a good idea to get ride of what seems to be overkill in my case (the c6) and lighten the load and strain of routine driving on my engine.

As for the gears i must have miss interpreted what i was reading elsewhere if you guys say your running similar gears. Ill have to double check exactly what i have and run the calculations.

So i am thinking aod over the c4 for this swap. I have read they can be kind of tricky/finiky when it comes to the kick down and such. Is there something i should look out for to avoid or pay extra attention to when putting in that AOD?

Could this be a fairly simple "driveway job" for myself and a helper who both have no real experience working with trans and such or should i look have it done by somebody?

Thanks for all the input and advice i appreciate the comments.

 

I thought I had posted this link already but I guess not.

Here is a link to the AOD swap I did and I explain how I set up the TV cable.

The Street Slammer Project Transmission

If you have any questions do not hesitate to email me.

Mark

 

I just took a second to check out the link, looks like that should be real useful, thanks for that...

 

Here is what I know. The Aod and C4 are shorter than the C6. You may need a different driveshaft. The Aod and C4 are pretty close in length though, so if you can find a donor truck that would be the best route. I know that the 80s Fords with 5.0s and Aods usually ran 3.55 gears for the 4x4. There are plenty of folks swapping 5.0s and/or Aods into mustangs, so there are throttle kits available. You also need to check your engine because Ford changed the balancing in 78 or 79. If yours is the one that came after the internal to external balancing, you will be fine(I'm not 100% sure of the details of this change, perhaps someone else here knows). If it is before, you will need a new flex plate. Again, this is a common swap for mustangs, so flex plates are available. I did know of a website that carried these parts, but can't seem to find it at the moment. Do some web searches and maybe something will turn up.

 

Oh, and the c4 or aod will be lighter than the c6, so with all the upside you may gain about 1 mpg with the aod...

 

I still have been looking for more info on this swap. From what else i have found...

The cross member used on my truck for the c6 will work for the AOD, but here are two things maybe you guys can clear up for me...

i read that the shift indicator wont work correctly and will need to be changed and or adjusted in some way but they didnt go into detail of what the problem was....

and finally the driveshaft, the AOD is shorter than the c6 i read i need a longer driveshaft, but i also read that the location of the tailshaft being lower than the c6 may mean no driveshaft problems.

 

the shifter arm is going to be about 3 inches too short. You can cut and weld in a 3 inch section or do like I did and just take a piece of flat stock and bolt it onto the shifter arm.
I don't remember if I mentioned that in my write up. I should re-read it.

Can't help you on the drive shaft issue. I had a shaft from a C4 so it just went straight in.