Aode 4r70w Transmission

[EveBYoung]

I have a few questions regarding this transmission swap.
Right now there's a james duff 3 speed manual on the floor.
The rig has a rebuilt 302, 3.5 inch lift (james duff ultimate kit, dual shocks all corners), 33 inch tires, 4.10 in the front 4.11 in the back, dana 20 t-case. Would an AODE 4R70W be effective in this setup? After doing some searches through this site it sounds like the rig might need lower gearing to make use of the 4R70W.
For a daily driver, lots of in town some highway, little bit of offroading (but not super intense), is the AODE 4R70W substantially better than the C4? The low first gear and the overdrive are really appealing to me, but I'd love to hear some feedback from ya'll.
Lastly, since as far as I know there is no full kit that can be purchased for the 4R70W, could someone list out all of the parts necessary for the swap (ALL THE PARTS ;D ) please? And exactly what mods would have to be made (I know of a few, but seeing it all in one place would be nice). Also, will the shifter fit okay along with a tuffy center console?
Thanks!

 

[Socal Tom]

Well, yes and no. With that gearing your engine is turning about 2700 rpm at 65MPH. With 4r gearing you will be doing 30% less, which brings you to about 1800 rpm. That's a bit on the low side for the 302. Especially if your someplace hilly and pushing big tires, and a 5000lb rig.

Now if you are going faster you may get to use the OD a bit more, but you won't really appreciated until you are running 4.56s.
I'm running 4.88s with 35s ( about the same as 33s and 4.56). I went from 3200 rpm at 65 to 2400. It made a world of difference.

You will also love the automatic off road, its much easier to drive than the stock 3 speed.
Tom

 

[EveBYoung]

is there anything i can do to maximize the benefits of the 4r without changing to 4.56s?

 

[dantheman222]

If you are running a stock Ford PCM for fuel injection there is a chance you can get that to run your tranny otherwise you would need to purchase a standalone computer. According to Wikipedia the only non computerized AOD's configured for 4wd were in the big broncos from 1982 to 1993. So this may be an idea. Then you would either need an adaptor to get the D20 on the AOD or run a NP205. I don't think the NP208 from the big bronco would fit...one from an F150 was too wide to go between my frame rails.

One more thought, you could possibly run a 2wd AOD since there were a billion of those and run a divorced D20?

 

[oleguy74]

you will be at about 3.60 gears in overdrive,maybe 3.50 with 33"tires.so no in my view.the 4rw70 is a little stronger than a c4.every thing you are doing is a compromise.give and take.by your post you won't extreme off road so you don't need the low-1-2 gear set if you go to 4.56.just my view...just need an adapter for 4r70w to d20.83-85 aod's get used a lot for the non-computer conversion.the 4r70w is better.

 

[dantheman222]

Scratch my stupid divorced D20 idea,

http://www.jamesduff.com/eb/shifters.html

As I understand it this adaptor could convert a standard 2wd AOD to hook right up to your Dana 20 and you would avoid the hassle associated with the computerized unit.

 

[localrich]

http://classicbroncos.com/tech/aode-4r70w-3-speed-automatic-transmission-guide

I have A 4r70w in our 66.

You'll need the trans either 2wd and the AA adapter or 4wd and the AA adapter. Either way you'll have to completely disassemble the trans so you might as well get it rebuilt. You'll need some way to control it we have the Baumanator. They make shifters now for the 4r70w.

 

[Socal Tom]

Read the transmission guide he posted. If you are willing to spend the money, you will get some use out of OD. You will definetly be able to use the lock up torque convertor. First gear is better than a C4, but you can get a c4 rebuilt and installed for a lot less than a 4r.

You can also convert an AOD to the 4R gearing, but I really think the computer controller is worth it. I was able to tailor the shift points exactally to suit my driving style, and it has a switch so I can have "tow/haul" mode or any other program I see fit.
Tom

 

[localrich]

I was able to tailor the shift points exactally to suit my driving style, and it has a switch so I can have "tow/haul" mode or any other program I see fit.
Tom

I prefer the "wife mode/bark the tires mode" on the programming ;D

 

[EveBYoung]

Well after doing some more research and looking at my budget I think I'm just gonna go with a C4 conversion for now and hold of on the 4r70w until I can afford it along with new gears (right after I can afford to upgrade to efi %) ;D ). Thanks for everyone's input though.

 

[EveBYoung]

Just out of curiosity, aren't 4.56s a little low for street/highway driving? If I do this in the future and want to use it as a daily/frequent driver around town, would 4.56s still be best? (I'm not familiar with how the overdrive affects the gearing so I'm sure you're right, just clarifying).

 

[Broncobowsher]

I run 4.88 with the 4R70W and 33" tires. Highway is no problem.
Take the axle ratio, multiply by the OD ratio, your effective gear is the result.
Try it, 4.56 x .70 =______

So 4.56 isn't too low for the highway. If you live in a fairly flat area, it probably is real good.

 

[70_Steve]

Well after doing some more research and looking at my budget I think I'm just gonna go with a C4 conversion for now and hold of on the 4r70w until I can afford it along with new gears (right after I can afford to upgrade to efi %) ;D ). Thanks for everyone's input though.

I'm not sure I understand your reasoning for going to a C4 first, especially if money is a concern. You'll be spending money for the C4 conversion that you will not be able to recover. You don't need EFI to run the 4R70W, and I don't think your 4.11s will cause a big problem. If the overdrive is too tall, don't use it... for now... You'll get a little lower first gear with the 4R70W than with the C4.

Just out of curiosity, aren't 4.56s a little low for street/highway driving? If I do this in the future and want to use it as a daily/frequent driver around town, would 4.56s still be best? (I'm not familiar with how the overdrive affects the gearing so I'm sure you're right, just clarifying).

A lot of the answer to this question depends on your engine, tranny, tire size, etc. Depending on how your engine is build (cam, heads, carburation, etc) there will be a "best" RPM for that engine to cruise. I run a 351 with an RV cam (low end torque), NV4500 (.73 overdrive) 4.56 gears and 35" tires. This combination has worked out perfectly for me. My engine is taching 2200 RPM at 65 mph, which is pretty much right in my engines "sweet spot", and still have plenty of RPMs left for passing, etc.

Use a Gear Ratio Calculator to investigate various tranny and gearing combinations. Lately I've been using this one. It allows for entering two sets of drivetrain variables, so you can compare.
http://www.grimmjeeper.com/gears.html

 

[EveBYoung]

Okay well now I'm beginning to reconsider again. After more looking around it seems I had underestimated the cost of the C4 swap.
Alright, so that I can do all the number crunching and figure out what I can afford - this is everything I'll need for the conversion from a 3 speed on the floor to a 4r in the column, right?
4R70W transmission
Computer
Adapter
Torque Converter
Automatic Transmission Starter
Transmission Cooling Lines
Carb Linkage Piece For The Kick Down Rod
Shifter Linkage
Flexplate + nuts and bolts
Harness
Automatic Transmission Steering Column
Shift Rod
Rod Mounting Pin

 

[Broncobowsher]

Okay well now I'm beginning to reconsider again. After more looking around it seems I had underestimated the cost of the C4 swap.
Alright, so that I can do all the number crunching and figure out what I can afford - this is everything I'll need for the conversion from a 3 speed on the floor to a 4r in the column, right?
4R70W transmission
Computer
Adapter AA AOD adaptor or a ZF adaptor if you get a 4WD 4R70W
Torque Converter Usually included with trans.
Automatic Transmission Starter
Transmission Cooling Lines
Carb Linkage Piece For The Kick Down Rodno kickdown, all eletronic
Shifter Linkage
Flexplate + nuts and bolts Make sure the flexplate is the right balance
Harness
Automatic Transmission Steering Column
Shift Rod
Rod Mounting Pin

TPS sensor and braket. There are some GM throttle body or ford throttle body parts that adapt nicely.
The Explorer shift arm needs to be lengthened to work
Driveshafts will need reworking
Crossmember needs replace or modify

 

[EveBYoung]

thanks a lot. sorry for being clueless haha

 

[DanWheeler]

I'm in the process of upgrading my manual NP435 to an automatic 4R70W. The costs pile up really quickly. New driveshafts, new alternator to run the new tranny cooler, new exhaust, new starter, new transfer case (or t-case adapter for you) new transmission controller, flex plate, headers, backing plate, throttle position sensor, shifter, etc etc etc.

here is my build thread in progress:
http://classicbroncos.com/forums/showthread.php?t=139552

There should be a lot of relevant information in there for you. I think its a good swap but it gets real expensive real fast. I'll be in at least $4000 when all is said and done. ($2200 of that is for the Atlas transfer case) Thats not to say you couldn't do it cheaper by sticking with the Dana 20 but your looking at $500 for the transfer case adapter, $500 for the computer and then several hundred dollars in misc parts.

 

[Socal Tom]

TPS sensor and braket. There are some GM throttle body or ford throttle body parts that adapt nicely.
The Explorer shift arm needs to be lengthened to work
Driveshafts will need reworking
Crossmember needs replace or modify

Also the potential for needing exhaust work.
Tom

 

[Socal Tom]

Okay well now I'm beginning to reconsider again. After more looking around it seems I had underestimated the cost of the C4 swap.
Alright, so that I can do all the number crunching and figure out what I can afford - this is everything I'll need for the conversion from a 3 speed on the floor to a 4r in the column, right?
4R70W transmission rebuild C4 is cheaper than rebuilt 4R/COLOR]
ComputerNot needed for C4
Adapter and labor to install out put shaftNot needed for c4
Torque Converter
Automatic Transmission Starter
Transmission Cooling Lines
Carb Linkage Piece For The Kick Down Rod
Shifter Linkage
Flexplate + nuts and bolts
Harness
Automatic Transmission Steering Column
Shift Rod
Rod Mounting Pin

C4 driveshaft lengths are the same as the manual tranny lengths, and your current exhaust system is more likely to work with a c4 than a 4R


You should be able to do a c4 conversion for less than $1000 if you shop for a complete bronco setup.
The 4R will cost at least $2000 unless you find someone selling a previously installed setup cheap.
Tom

 

[firehawk]

Baumanator.com has some good info and products.