Help Choosing Auto Transmission


Jan 11, 2015
I am planning to swap out my T-5 manual for an automatic transmission (yeah, yeah, I know). I currently have a '65 Fastback, Ford Racing Crate 306 (340 hp) with EFI, 9" Versaille rear axle, Total Control front front end, power steering and brakes.

I am looking for opinions on what type of automatic transmission to put it and where to get it. I am military so i move a lot and cannot nail down a reliable mechanic. Seems like everyone has an opinion (on why not to do it, and what i need to do... but that's not what I looking for).

Thanks in advance.
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SN Certified Technician
Apr 12, 2002
depending on what you are wanting from the car, i will give you two recommendations;

1: for a city vehicle with very little highway use, and perhaps some race track time, a C4 built by someone like B&M or monster transmission will do nicely, especially if you limit your rear gear to 3.50-3.89 gears.

2: for some highway use, city use, some track time, and lower gears than listed above, an AOD built by someone like lentech or silverfox with a modified valve body shift pattern would be a good choice.

my preference would be for the AOD with a modified valve body, to include a constant pressure valve body to avoid issues with the TV cable adjustement, and modified shift pattern.


Founding Member
Jul 13, 2002
Austin TX
Rbohm knows his stuff, listen to him. The thing I want to add is...if you choose AOD (I did) there's a lot of extra work (and some added expense beyond the tranny) compared to choosing a C4.


Nov 7, 2017
I'm new to this forum so I don't really no anybody here I was a trans builder for many years first if you want to go automatic I would run at least 3.89 gears the aod would probably be the best choice with a few upgrades rbohm mentioned the constant pressure valve body I would start there most important is your converter don't try to guess on a stall speed you can get close spend the money here and have one custom made there's a lot more but depends on how deep your pockets are you might think about the 4r70 I believe it would require a stand alone system I'm running a c4 in my 68 behind a 429 with no problems just no overdrive maybe a gear venders some day
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