It looks like my AOD is on it's way out http://57fordsforever.com/smf/index.php?topic=7133.0 so I'm considering my options. Automatics of any description aren't popular over here with over 95% of cars being manual, so auto transmission specialists aren't in every town, meaning hands-on expert help isn't easy.....
I'm considering my options transmission-wise and I'm torn between having the existing AOD rebuilt, buying a new one or going for something like a C6. I like the fuel economy benefits of the AOD but I'm concerned that it requires a bit more than a home-mechanic and spanners to get it "right", hence wondering about the C6.
Any advice/opinions?
Thanks
If you can build a C6 or C4, AOD is no problem. There is one specialty tool for measuring the one and only thrust washer and a set of lip seal cones. There are a bunch of offering on the internet. Comp Cams just bought up TCI Transmissions. There are a couple of good 'how-to' books with lots of color pictures, specs, and stock and performance builds. I like C6 and C4 but no fourth gear. Around here, finding a donor C4 is getting tough. C6 is a little big but is easier to find and will need drive shaft and flexplate changes.
I went into the deep end with my AOD because I wanted to and I'm going to run it harder than you. A well built, stock AOD with a couple of upgrades will perform well for many years.
I'm no tranny expert by any means, but it seems to me going to a c6 since your car is already set up for an aod would be a step backwards. The AOD powered probably millions of Fords over this side of the pond the many years they were used. The AOD spawned the AODE then the series of 4R70w's, but the AOD is not computer controled as the later kin are.
Not only would you need to change your driveshaft length but the rear gear ratio would need to be changed. I went with the AOD but considered the other options. I love having the OD but had some difficulty getting mine to shift right, now that I have that working right I would not downgrade to a C4/C6 unless it was to a manual 4 speed. Good luck in your decision, I feel your pain.
If your engine is a 302 like I think it is a C6 is overkill for that engine. Plus it's a real tight fit in the trans tunnel of your Ranchero. To make mine fit with a bit more room I trimmed the outer ribs on the trans case for more clearance. There a great transmission, but they do soak up a lot of horsepower to run, like around 40-50 hp. I just dont see the need for a c6 behind a mild small block.
If it were me I'd be either rebuilding the AOD or buy a c4.
Thanks, I didn't realise the C6 was such a big difference to the C4. Well, after a bit of research it turns out that some European Fords used a variant of the AOD (the Ford Scorpio was one) and some of the English transmission specialist are set-up for them so I'll go with having my existing one rebuilt over winter.
Thanks for all the advice.
Yes Gary, some of the German Fords of the 70s and 80s and 90s used C4 and AOD variants. ( Granada, Taunus, Scorpio,2L Sierra).
The AOD is a very nice daily driver transmission and fairly well suited for a 302, as you keep high rpms in low gears with a fairly high geared rerend. the 302 is a revving engine. final OD gives you good milage on the highway, a very good combo. a C4 is of about the same size but leaves you with high rpms on the freeway.
I have 2 AODs here that I plan to use in my cars. for now it's C4 and fordomatic.