C-6 Tranny...

007_SuperCoupe

Registered User
I was just wondering if a C-6 tranny would bolt up in place of our AOD. I know that you have to build an adapter plate for the shifter and some adjusting to get the indicaters on the shifter to line up with the gears in the tranny. I've got a C-6 (and a 351W) from an F-150 that I'd like to get in a bird. And I know that the C-6 is a very durable tranny (much more so than the AOD). If the 3.8 bellhousing bolts up the same as the 5.0, but does the 5.8 (Windsor) have the same bolt pattern as well? I think that it does, but I just want to make sure. Thanks.
 
The aod built properly will hold up to over 1000hp..I had one in my 748rwhp cougar..Hell its still there..Nowwwwwwww full throttle in OD..nahhhhhhhhhhhhhh
 
I'm aware that the AOD can be built to handle that amount of power. However, the cost of building one up to handle say, 300-325 rwhp far outweighs the cost of a C-6 rebuild. The C-6 is already made to handle that amount of power. I'm just looking for cost effective alternatives to help the performance of my SC.
 
Well if you want to really look at it then it will probably end up being the same with the mods you'll have to make to get it to fit. Bellhousing will need to be changed or get an adapter. Then the linkage doesn't line up, don't know what to do about that. Also if you intend on going with a different tranny w/o OD then look at the C-4 instead of the C-6, a lot less loss of horsepower through it that a C-6.
 
I ask about the C-6 because I have one. And I'm not too sure about the belhousing. For instance, a T-5, AOD, (and AOD-E) and the later model electronic version of the AOD-E (can't remember the alpha-numeric designation) bolt up the same on the 3.8 and the 5.0. I'm pretty sure that the 5.0 and the 351 windsor have the same bolt pattern for the bell housing, but not positive. I do know that there are many parts that are interchangeable between the 351W and the 302 (302 HO for the proper firing order). What isn't are the lower intake manifolds (for FI or the intake manifold for carbs) the crank and rods. The pistons, heads, cam and virtually anything else will bolt right up.

I know that most C-6 trannys were put on big blocks, but there were a few that were put on small blocks, specifically in the F-150 with the 351W. This is the tranny that I have. I don't think that there will be too much in the way of mods to the tranny that I will have to other than I have mentioned before. I'm just hoping that some one who has some fairly extensive experience with the C-6 trannys can confirm or deny my thought pattern. I'm looking for more concrete assurances rather than speculation.

As for the cost, well, by rebuilding the C-6 myself and working with the adapter for the shifter as well, I can save a significant amount of $$. I'm sure that there may be a few hidden expenses, but on the whole, relatively inexpensive (less than $1k estimated I think on the high side) as opposed to the AOD which could cost upwards of $2k just for the parts to rebuild it. I'm eventually going to put the 351W and the C-6 in a MN-12 bird. In the meantime, I'd consider this R&D.
 
Well, I know it can be done but I'd guess there would be as much as a 30 rwhp difference between the two with a modded SC. The C-6 just has bigger parts in it and it takes more power to turn them. I also think the C-6 wieghs like 30 lbs more. As you can see I wouldn't do it, even if it does save you $500. Is it worth it to save the $$$$ to only lose 30 hp and lose OD? If you really want to do it then find a built C-4 used for around $500 and that should keep you in your price range, or even a new built one for around $750. Oh and an adapter should only run $100 at most since a lot of Mustang guys do the switch.
 
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Just found this for you

AOD/C3/C5 to C4/C6
The C4 has long been known as the drag racer's special. This bulletproof 3-speed transmission really wakes up the powerband in your Cat's motor in the quarter mile. For the 5.0, virtually nothing needs to be changed---the mounting pattern is the same (provided the bellhousing is set up for a small block Ford motor). You will need to shorten the driveshaft with this swap. The transmission crossmember must be changed to accommodate your new C4, using FRPP's C4 crossmember (p/n M-5059-A). You will also need to buy a new flexplate from FRPP, p/n M-6375-E302 (157-tooth, 50-oz imbalance, for all 1981-up 5.0 V8's). Since the C4 was found in some early-80's Fox cars, it's a nice fit. If you don't really need an overdrive for your car then this is the transmission to get. (Thanks to Royce for the part numbers above).

The C6 is also a very dependable transmission. But keep in mind that the C6 is physically a very big transmission and some tunnel "modification" (a.k.a. the BIG hammer) is needed to get it to fit. It is reported that the driver's footwell must be cut out for the linkage for the C6 to fit properly; a simple cover plate can be welded inside the car to cover the hole. Realistically, the C6 is best used for severe-torque motors (such as the Ford 460) and is a bit much for the daily commuter.
 
Thanks Arron for the more specific information. That is indeed what I was looking for. The more that I think about it, I may actually have a C-4 instead. It is actually at my old man's house still in the truck. I remember as a kid he sais it was a C-6, but I'll have to double check when I'm there this weekend. Thanks also for the part #s to get the C-4 to fit. Either way, what ever he has there, I'm putting into an MN-12 bird eventually and this info should help in that process, which is what I was looking for. Thanks again.
 
I double checked this weekend on the tranny. And it is a C-6 bolted up to a 351W. The C-6 will fit nicely in our MN-12 birds. I spoke briefly with pro_street_rich who confirmed that only a mounting adapter plate is needed and it will bolt up directly to the tranny x-member. I'm not too sure about the driveshaft, but I seem to remember him stating in a related post that the driveshaft would have to be shortened. The only problem with trying to bolt up a C-6 is that the bell housing cannot be changed. Wrong bolt pattern and it won't work without more extensive work. My question has simply been about the bolt pattern; 351W the same as the 5.0 the same as our 3.8s?
 
hey while you are at it replacing the AOD with a 3 speed automatic, maybe you can 'upgrade' to a carburetor , points ignition, and drum brakes all around too!.......you dont need all the new fangled crap they hung on the SC! let me know how you like driving it after you do all those mods , okay? :)
 
Tranny

I just happen to have a Small Block Bolt pattern C6 sitting in my garage. Same bolt pattern as the 3.8/4.6/5.0. It doesn't have a Converter and might need to be gone through being it's been sitting in the garage for 2 years. I was going to install it in my 90 SC but decided to just rebuild the AOD that was in it instead. Your interested send me an Email we can work something out.

monsterop@insightbb.com

(and for those who say they dont make a Small block C6, they do between 70-73 the used them in vans with the 302's)
 
Thanks for the offer, but I already have one. And I'm pretty sure that the one I have is the small block bolt pattern. Besides, I think that I am going to put my effort into rebuilding the 351W that I have (stroked to 392) and go from there. And Ford was putting C-6's on various small blocks well into the '80s. The C-6 I have is from an '86 F150. I'm toying with the idea of building up the AOD to handle the 351W too. I'm pretty well keeping my options open as of now.
 
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