OD for 71 Fury

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This winter I would like to do a rear gear swap and OD tranny. My 727 leaks like the titanic and it needs steeper gears (currently 2.71) . I would like to do 3.90 or 4.11 with the OD swap. I haven't found any rh42 or 46 around on Craigslist or Junkyards but plenty of GM200r4 and 700r4 (and 4l60e but the E scares me) I want simplicity. I also want something that can be built and if /when I do a big block swap it can stand the abuse. Plenty of guys making power with the GM trannys I also have a guy around here that will build a Ford Aod with convertor and ultrabell for 3700$ but I dont want to really drop that much coin if I dont have to... They also make the ultrabell for the GM trannys and I found a TCI adapter
TCI Auto 149160 - TCI GM Bellhousing Adapters
plate ... has anyone gone this route with success? What are the benifits or is the ultrabell better ? Is the 42/46rh swap easier and can they be built on the cheap and still be able to swap to big block bellhousing in the future? Lotsa plans and a slim wallet.
 
See www.gearvendors.com/hrdodge3s.html. The ultrabell conversion in my opinion is a waste of money when you can rebuild your existing A-727 and bolt the overdrive conversion on the back of it. The tail shaft will be long and you will need a shorter drive line but that will be the case with any OD conversion. The A 727 is also stronger than any of the Ford or GM transmissions.

Dave
 
The THM200-4R has seeming become the darling of the street muscle people. Takes less power to run (which is probably why it was behind the SC3800 in the Turbo Regals) and with aftermarket parts, stout enough for a big block Chevy V-8 (and by default, a stout 440), but with aftermarket innards. BUT to use any non-Chry transmission might trigger TISSUE REJECTION!

Adding the external OD unit is pretty easy to do. What about driveshaft tunnel clearance? To me, this might be about the same as the older Dodge diesel 727/OD trans. Same gear spacing plus the switchable OD (as the Chry unit also could be).

There is a thread in here that details how to adapt analog pressure switches to the 6-spd TF to run the electronic valve body without an external "box". To me, that would be the best option. But it would need the bellhousing adapter, too.

This "upgrade" is not going to be terribly inexpensive. Build the trans, spend about $500.00+ for the rear gear change, and you'll probably spend several thousand dollars by the time you're done. No way to justify that with fuel economy savings, if that matters. If you want to be "pushed back into the seat", installing softer seat lean-back springs might be an option.

CBODY67
 
Fuel economy cant be a major concern for a 4000lb car. The seats are plenty soft ( it's like grandmas couch ). Everyone wants the best of both worlds I'm no exception. Right now with the 2.71 it's a pig from a light. I have a Ford 9 inch center section with 3.55 which will make a dramatic improvement but I hate doing EVERYTHING on this car 3 times ( although that's the benifits with the removable center section change it in a few hours)..
A few grand I could deal with I just would like the ability to if/when I go big block to be able to (without starting over ) make the swap simply. To have the 727 built isn't a big deal but then it has a small block bellhousing . The gear vendors unit , I actually HAD a lead on a used 727BB with the gear vendors for 1k but the BB scared me I wasnt sure if it could swap over . And I figured there should be a better alternative than buying an unknown condition 727 and gear vendors to hope it would work.
The ultrabell option seems like the best bet as I could build a 200 or 700 or aod and always swap the bell and go.
The guy by me is building AOD to hold more power than I will ever want to make in this car. At 3700 for the tranny , convertor, and ultrabell its also a little steep . Still gotta cut the shaft , figure out the linkage and hopefully not modify the tunnel by without getting to the rear I can be at 5k in a hurry.
 
Thank you wish4hemi ,I will thumb through this in a little bit
 
If you are still running a small block engine, get a late 80's early 90's A500 or 518A from a Dodge 2wd pickup. It has the push button OD and bolts in with some mods to the trans mount but none to the floor and cut the driveshaft.
Just add the OD button anywhere in or under the dash.
3.55 gears work best in a C with a 318 or 360 with an OD trans.
It was done before in a members car called Polaraco a 72 Polara 4dr with a MPFI 360 and a518 trans.
 
The GM 200 trans is a POS okay behind little motor in little car (where it was born). Everthing can be upgraded in it, by the time you spend that money you could rebuild a 727 and add the GV OD. The 700r4/silver sport is okay, but with every 700/4L60 the 3-4 clutch pack, plastic accumulators/servos, and the splines on the rear drum are ticking timebombs, easily uprateable with a Z pack and a aftermarket drum, and aluminum pistons, but it has to come back apart.
The 500 & 518 Chrysler OD is a piece of crap and not worth the time unless you put 4.56 rear gear and very short diameter tires.
 
The GM 200 trans is a POS okay behind little motor in little car (where it was born). Everthing can be upgraded in it, by the time you spend that money you could rebuild a 727 and add the GV OD. The 700r4/silver sport is okay, but with every 700/4L60 the 3-4 clutch pack, plastic accumulators/servos, and the splines on the rear drum are ticking timebombs, easily uprateable with a Z pack and a aftermarket drum, and aluminum pistons, but it has to come back apart.
The 500 & 518 Chrysler OD is a piece of crap and not worth the time unless you put 4.56 rear gear and very short diameter tires.

I thought the A518 was basically a 727 with the OD added on in the tailshaft ....

https://transmissioncenter.net/shop/727-to-518-transmission-swap-information/
 
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You are correct in part, the A519 and A727 shared a lot of components. The main problem with the A518, which was the heavier duty truck transmission, was the lock up torque convertor. If you want to use the A518 you have to use a locking convertor which was the cause of most failures. Friction material on the convertor disintegrated over time and spread friction material thru the rest of the transmission destroying the overdrive assembly and bearings. A better choice is the add on overdrive assembly on the A727 while keeping the non locking convertor. That combination is much more reliable.

The A500 is the locking convertor version with overdrive of the A-904.

Dave
 
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I used 1994 46RH 4WD auto trans in my 1990 W150. Been a great trans for 50000 miles.
You are correct in part, the A519 and A727 shared a lot of components. The main problem with the A518, which was the heavier duty truck transmission, was the lock up torque convertor. If you want to use the A518 you have to use a locking convertor which was the cause of most failures. Friction material on the convertor disintegrated over time and spread friction material thru the rest of the transmission destroying the overdrive assembly and bearings. A better choice is the add on overdrive assembly on the A727 while keeping the non locking convertor. That combination is much more reliable.

The A500 is the locking convertor version with overdrive of the A-904.

Dave
I thought the A518 was basically a 727 with the OD added on in the tailshaft ....

https://transmissioncenter.net/shop/727-to-518-transmission-swap-information/
Yes it is. Let's be clear though the cone clutch .69 overdrive is crap. It's weak has bad oiling and .69 is waaaaay to tall. The hydraulic units with mechanical governor are okay and can be dealt with to make good shift points A&A transmission would be your best friend on this setup. The 97up units with electronic speed governor (PCM controlled shift points) are the worst things ever, and grafting it into a vehicle without the PCM would be a nightmare.
An early one with OD and lock up converter on manual switches and a Trans Go shift kit would be tolerable.
They are also a ginormous transmission in anything but a truck. How much do you value your pristine floor pan. Your completely on your own for fabbing the cross member.
I feel it would be the worst choice of all and has very little in the way of aftermarket support unless you can make your small block think it is a diesel.
I personally would not put it on the list of possible choices
 
You could go really outside the box with an 8HP70 8 speed...

318/8 Speed Swap
I reached out to Sound German. They make a controller for the 8hp70 . They said I would need a shifter as well...That sounds like a great option. I could find a used tranny for under 1000. The TCU is 1000 , shifter 150 . Cut driveshaft and other fab work ( which i would have on any other route) I could be all set for under 3k . About the same at the gear vendors. I'll do some more reading/research but I REALLY like that option
 
I reached out to Sound German. They make a controller for the 8hp70 . They said I would need a shifter as well...That sounds like a great option. I could find a used tranny for under 1000. The TCU is 1000 , shifter 150 . Cut driveshaft and other fab work ( which i would have on any other route) I could be all set for under 3k . About the same at the gear vendors. I'll do some more reading/research but I REALLY like that option
Nothing wrong with a gear for any situation.
 
Yes it is. Let's be clear though the cone clutch .69 overdrive is crap. It's weak has bad oiling and .69 is waaaaay to tall. The hydraulic units with mechanical governor are okay and can be dealt with to make good shift points A&A transmission would be your best friend on this setup. The 97up units with electronic speed governor (PCM controlled shift points) are the worst things ever, and grafting it into a vehicle without the PCM would be a nightmare.
An early one with OD and lock up converter on manual switches and a Trans Go shift kit would be tolerable.
They are also a ginormous transmission in anything but a truck. How much do you value your pristine floor pan. Your completely on your own for fabbing the cross member.
I feel it would be the worst choice of all and has very little in the way of aftermarket support unless you can make your small block think it is a diesel.
I personally would not put it on the list of possible choices

I'm pretty sure the earlier manual valve body will fit an electronic controlled 46RE because the case is the same as the RH. If you can live without the auto function you could actually have a 6 speed as the OD is on a switch.

Kevin
 
I have an a500 living behind my turbo 383 boosted at 12psi now.... They must not be total junk...
No floorplan work, but yes a new cross member.
That said, if you're staying sb now and want bb later I'd consider the GV.
 
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