Should I try again?

[bax]

Yep I am thinking about an overdrive for the bronco again. Some of you know I have killed a few AOD's and gave up on them. I am running a c6 now that works great But, The overdrive is missing. When I built the bronco I geared it for overdrive. So now it is a bit over geared. I talked to a guy last week about building me a 700r or another aod with 4r70w internals. The truck is already apart. I am putting a hi 9 rear into it. The guy said he could build it to handle 500 hp / tq. I am a little unsure about trying the aod again. The 700r is way more money but it would also hold up like the c6. The c6 works great, stays in 2nd gear a little to long but it works good.

 

[blubuckaroo]

The GM tranny will cost to adapt but you should be able to get a 700R4 built better than any Ford tranny and at less money than a Ford tranny. My transmission shop owner told me he wished all Ford owners would make the swap cause Ford overdrives are a lot of trouble. Are you using an Atlas?

 

[firehawk]

I am curious as to the motor you have in your bronco. The AOD can be built to handle plenty of power. I had one in my supercharged mustang and so did a friend, his car was stolen and missing for about a month. We heard it racing down the expressway which was nearby but did not know it was his car until we started hearing stories about who stole it and what they had been doing to it.

Brand new slicks were wasted and they spray bombed the whole exterior brown primer. Other than that and the ignition the car was fine including the trans.

His car was a supercharged high ten second car and was beat like it was stolen and the trans held up fine.

The guy that builds them machines some extra clearance for additional clutches and other secret upgrades and they are strong.

I am sure you have an external cooler for it too?

 

[73stallion]

just for kicks, make a call to dana sniff out here in cali. 949-559-6563. he builds lots of transmissions for racing and high horsepower apps, he's talked to me about building an ultimate AOD with 4R70W guts. if anybody can do it he can. he's got a good reputation on here too.

http://www.mypowerblock.com/profile/DanaSniff

 

[brewchief]

I'd like to see an AOD work for you but I would make sure it was all top shelf stuff and had a money back guarantee.

A lot of people like to compare transmissions by what there buddy has run in a drag car, I don't think that is a fair comparison. A drag car may be in each of the lower gears for a few seconds but in a off road rig you might run around all day in 1st or 2nd gear and you might end up at WOT in one of the lower gears or reverse for twice the time the drag car is on the track or longer.

 

[sprdv1]

Might as well giverrr a shot Bax..

 

[gravy]

I am running my AOD with 4R70w internals for the last few years- no issues and wheel it pretty hard, hits the highway occasionally. Running the cooling system separate from the engine and it has its own fan- the engine coolant heats up the trans to much

 

[surfer-b]

My only complaint with the OD's is the gap from 3rd to OD, its just too much, I have one in my Ranger and its ok. I like the gearing I have for 1-3rd but its too high for AOD, the AOD goes from a 1.1 3rd to a .68 OD. I'm not sure what the other AOD's are I dont think they are as much of a gap but close, which makes it almost useless unless its perfectly flat and no head wind. I would like to have one with a .8 OD, I think it would work much better with the body style of the EB's. Other than that I have no complaints however I dont wheel my Ranger and do not have high HP. I left the c4 in my 76 and about to do a 2000 explorer conv, I'm gonna leave the c4 in mainly for simplicity. Thats my take I know that doesnt really help ya any so take it for what ts worth.

 

[Apogee]

Are you looking to avoid electronically controlled options like the 4r70w or 4L60/65/70E?

 

[blubuckaroo]

The gear ratios of the 700R4 are better suited for a Bronco than the Ford counterparts. A lower first/second gear and an overdrive that isn't way too high like it was made for a car. The only problem I see is the temptation to eliminate the bell housing adapter and complete the improvement with an LS1 motor.
Here's the CB comparison.
http://classicbroncos.com/tech/700r4-4-speed-automatic-transmission-guide

 

[lowbush]

Has anyone tried one of the ZF auto's that they put in the Range Rover and Defenders. They are pretty cheap and bullet proof. I don't know if they make an adapter to the D20, but I know over the years the Range Rover bolted it up to quite a few transfer cases, IIRC they have the same drop as Ford. Might be an option, the ZF autos can take a whole lot of torque and you can pick them up used for $300 - $500 bucks with transfer case.

 

[broncodriver99]

Has anyone tried one of the ZF auto's that they put in the Range Rover and Defenders. They are pretty cheap and bullet proof. I don't know if they make an adapter to the D20, but I know over the years the Range Rover bolted it up to quite a few transfer cases, IIRC they have the same drop as Ford. Might be an option, the ZF autos can take a whole lot of torque and you can pick them up used for $300 - $500 bucks with transfer case.

I looked at the zf4hp22/24 when I was contemplating my diesel swap. They have their flaws as well. They have a reputaion for burning up if you tach the engine up while in park or neutral. They do require a controller.

 

[bmc69]

The one 700R4 conversion that I and a buddy did on his trail rig was a major PITA to get right for heavy trail use. It would overheat something awfull. Ended up solving the problem by locating a guy who understood exactly how tobuild a custom torque converter for it that had a really extreme clutch pack design.

Once that problem was solved..one sweet-performing setup.

Oh..and the Lokar shifter (the only option we could find for it) required a fair amount of modification to make it mount properly.

 

[lowbush]

I looked at the zf4hp22/24 when I was contemplating my diesel swap. They have their flaws as well. They have a reputaion for burning up if you tach the engine up while in park or neutral. They do require a controller.

Yeah I did not mean to imply that they are not without their flaws, just they are a far better transmission than the stock 700R4. I know in my Defender it was about the only part worth a crap.

 

[broncodriver99]

Yeah I did not mean to imply that they are not without their flaws, just they are a far better transmission than the stock 700R4. I know in my Defender it was about the only part worth a crap.

I agree they are definitely a better tranny than the 700R4. The reason I ultimately decided against it was that Ashcroft over in the UK was the only shop I could find that could build and tune it to hold up to the diesel. As far as a gas job they should be ready to go in stock form.

I would think the AOD w/ 4r70w internals should hold up just fine though.

 

[bax]

Being the matco tool guy I have a chance to talk to my transmission shops about this decision. Almost all of them like the 7004r better than the / any ford transmissions. ( Non computer) Bill I would be interested in the converter specs. Also how is the pan clearance and the front cv joint. Looking more and more like a 700r4. I am thinking I need to learn up on the 400 r4 conversion. Anyone want to help learn me?

 

[lowbush]

Being the matco tool guy I have a chance to talk to my transmission shops about this decision. Almost all of them like the 7004r better than the / any ford transmissions. ( Non computer) Bill I would be interested in the converter specs. Also how is the pan clearance and the front cv joint. Looking more and more like a 700r4. I am thinking I need to learn up on the 400 r4 conversion. Anyone want to help learn me?

You need specifics on the conversion or the transmission. I can help you on how to build a 700R4, but don't know anything about putting them into a Bronco. If you need help with the tranny itself, let me know. If you have an option on which 700R4 go for one that is 89 and up. In 88 they changed the valve body and in 89 they changed a few more items. 89 and up are much better. Also if you can get the 700R4 in then you should be able to run a 4L80E which you can built a mechanic non-electric one with a kit like TransGo, for not too much money. The 4L80E is definatly a stronger tranny stock.

Also, if you have not seen this article, it has a lot of good info on the subject: http://www.700r4inaford.com/