Aod Or 4r70w? Which Is Better?

I'm trying to pick a transmission for my car.I thought about going with a magnum t56, but had a change in heart and want to go auto. I can't tell which is the better transmission, AOD or the 4r70w? my car specs are on my sig, but want something to hold about 800hp for next time I upgrade the engine. I do mix street and strip, about 50/50, and was thinking of a luck up convertor. I am going to build it myself as well. does anyone also know what is done when the big companies say " Clutch cylinders modified for extra clutches"?
 
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so it sounds like a non lock up convertor would be ok. My other question was, when i look at company web sites that build performance transmissions, they mention "Clutch cylinders modified for extra clutches"? What do they do? I hear nothing but adding clutches on other forums but not having to modify anything.
 
so it sounds like a non lock up convertor would be ok. My other question was, when i look at company web sites that build performance transmissions, they mention "Clutch cylinders modified for extra clutches"? What do they do? I hear nothing but adding clutches on other forums but not having to modify anything.


What they mean is they've modified the clutch packs (special machining) to allow more steels and clutches. The more clutches and steels there are, the better the clutch pack grabs. Also, I would go with a lock up converter if you're getting the 4R70W. It's a fully electronic transmission. You'll have to get a transmission controller. The trans controller will dictate when lock up should come in using the various readings it will take in such as throttle position and output shaft speed. So you won't be in lock up while it's shifting gears. Anyways, lock up only comes on in 3rd and 4th gear (unless you wire it up on a toggle). Even with a manual valve body you won't be in lock up all the time. How would you expect to be able to come to a stop with it in gear and it still be running if the TC was locked up solid? It'd kill the motor instantly.
 
And the reason I say that you need a trans controller is because there is an electronically controlled motor in the transmission that dictates line pressure in the trans. You can't just slap on a manual valve body and be able to run it.


ALSO one final thing. If you do go non lock-up, run a big ass cooler like previously stated. When a converter isn't locked up, it is essentially slipping. Slipping causes friction which causes heat. Heat is the number 1 cause of transmission failure. Run you a big external cooler. Hell even if you get a lock up converter, get an external cooler. You're running quite a bit of power. You want that trans running as cool as possible.
 
Thanks for the input. I got a little confused though when you said " You can't just slap on a manual valve body and be able to run it". I thought that you could just slap in a manual valve body and forget about the electronics?
 
You need all the electronic inputs to dictate line pressure. There is no throttle pressure cable. Line pressure in the trans is electronically controlled.

The electronics are not just for the shift points.
 
ok, that kind of sucks. I wasn't planning on an extra $500 over what I already priced out for the build, but no biggy. Well then, I guess I'll look into a baumann controller too. Or is there something cheaper to just control line pressure?
 
I'm really not sure on that. I haven't read MUCH on aftermarket controllers.
But what I have read, it's always good things about the Baumann controllers. I was gonna buy one when I wanted to swap an E4OD into my F150
 
so I gave a call to one of the local performance shops today. They were telling me that in an electronic trans, it is the electronics that control pressure, but when you put in a manual valve body, you are getting rid of all the electronics in the trans. Pressure is then determined by the pressure regulator valve in the valve body. So I guess we both learned something new here.
 
so I gave a call to one of the local performance shops today. They were telling me that in an electronic trans, it is the electronics that control pressure, but when you put in a manual valve body, you are getting rid of all the electronics in the trans. Pressure is then determined by the pressure regulator valve in the valve body. So I guess we both learned something new here.
Yeah I definitely did learn something new! Actually very nice to know.
 
My friend uses a AOD in his low 9 sec. (9.37@148) 93 Mustang drag car. Has been in the car for 3 years now with nothing more than annual fluid changes. Very reliable. Came with a 2 year warranty rated for 1000 hp. We are putting at least that much through it now with no issues.
 
My friend uses a AOD in his low 9 sec. (9.37@148) 93 Mustang drag car. Has been in the car for 3 years now with nothing more than annual fluid changes. Very reliable. Came with a 2 year warranty rated for 1000 hp. We are putting at least that much through it now with no issues.
That's why I don't understand why the AOD gets so much flame...
It's not a bad transmission, even when it has a "factory" style rebuild. And the 4R70W and the 4R75W are basically newer generations of it. So obviously something about it, Ford liked enough to run it for years after.

It's like GM's 700R4. Get's a lot of hate (I personally don't like them) but GM changed them to electronic controls in '93 and ran them (updating them along the way of course) way up into the 2000's. The 4r70W and 4R745W are to the AOD as the 4L60E and 4L65E are to the 700R4.


Oh and OP, if you get a manual valve body, you can wire up the lock-up to a toggle. You'll have to with overdrive as well since OD was on a button in the cars originally.
Your shift pattern will be (depending on if you get reverse pattern or regular) PRN321 (or PRN123 if you go reverse pattern) with OD and lock-up wired to a toggle.
 
The AOD isn't that bad. The 4r70w drum is used to hold more clutches in first. You can beat the piss out of the AOD as long as you don't overheat it. Once you get rid of the slush box characteristics they can hold decent hp.
 
The AOD isn't that bad. The 4r70w drum is used to hold more clutches in first. You can beat the **** out of the AOD as long as you don't overheat it. Once you get rid of the slush box characteristics they can hold decent hp.
Yeah my dad built one for a buddy of mine and it had awesome shifts. It'd bark the tires hitting 2nd gear
 
I was originally thinking about going with the aod, but seeing that the 4r70w was close to the same price to build, it really started to push me in that direction. The bonuses are the od and lock up feature. I heard you cant run a lock up convertor on the aod if you have a lot of power cuz you have to upgrade the shaft and it nobody makes a built lock up shaft for the aod. My car will be driven on the highway enough to justify the od at least. The drag strip is about 25 miles away, all highway, and of coarse weekend cruises.
 
I was originally thinking about going with the aod, but seeing that the 4r70w was close to the same price to build, it really started to push me in that direction. The bonuses are the od and lock up feature. I heard you cant run a lock up convertor on the aod if you have a lot of power cuz you have to upgrade the shaft and it nobody makes a built lock up shaft for the aod. My car will be driven on the highway enough to justify the od at least. The drag strip is about 25 miles away, all highway, and of coarse weekend cruises.

I have OD in mine. There's alot of speculation of Lockup vs non lockup.(Mostly fuel economy and heat) They do make hardened input shafts for the AOD as well.