dodge big block overdrive trans?

oxbronco

Active Member
Does any one know if dodge ever built an overdrive auto trans that would bolt to a 440 engine? I was also thinking of getting one of those gear vendor overdrives, does anyone have any experience with those?
 

Tacoma

Et incurventur ante non
Location
far enough away
I would think the 46 or 47 RH trannies would bolt up? The RE trans need an electronic controller. GV overdrives are expensive as heck, and pretty long too, but they work very well. I"ve towed with one and they're pretty sweet for splitting gears and idling down the road. :D
 
now dont hold me to this but a buddy 70ish camper that had a BB440 with a 727 with sometype of over drive or splitter on the tail shaft. now this was eather factory or dealler installed. he was not the origianl owner so he cant say but it worked like a overdrive.

maybe its the same thing tacoma refering to, but is was on a 727 im sure of that. sorry thats all the real info i have and that campers probally a toyota buy now so i cant even get a picture.

jason.
 

Rot Box

Diesel and Dust
Location
Smithfield Utah
I'm no Mopar nut, but isn't it possible add a the A518's O/D (seperate rear section) to a TF727 to make a hybrid? My brother has the TF727, and had an overdrive added internally somehow... I'm pretty sure that's what they did, but I'm not certain :-\ He upgraded to a push button torque converter lockup (A518's and TF727 didn't have a factory lockup), and it now has a push button for the O/D.

My other brother has the gear vendors overdrive in his four door F350 with a 5.9 Cummins and the Ford C6. The thing is a mile long even on the four door the rear drive shaft is really short. It's kind of cool but they are expensive for what you get. That being said you would be better off going a different route imo.
 

Meat_

Banned
Location
Lehi
I'm no Mopar nut, but isn't it possible add a the A518's O/D (seperate rear section) to a TF727 to make a hybrid? My brother has the TF727, and had an overdrive added internally somehow... I'm pretty sure that's what they did, but I'm not certain :-\ He upgraded to a push button torque converter lockup (A518's and TF727 didn't have a factory lockup), and it now has a push button for the O/D.

Puhleassse find out, I've got a Ramcharger that will someday be done up with a big block and it would LOVE to have an O/D
 

oxbronco

Active Member
Thanks for the info, Im going to talk to my trans guy and see if he knows anything about the 518 thing. I was also thinking about getting a trans adapter and bolting in a small block trans with overdrive, im just worried about getting the thing wired with them being electronically controlled. yeah, I looked more into the G.V overdrive and they are like 3 grand so I dont think I will be going that route. Im running 37's and 5.13's I love the power, but the engine is screaming at 65mph.
 

tv_larsen

Well-Known Member
Location
Logan, Utah
Does any one know if dodge ever built an overdrive auto trans that would bolt to a 440 engine? I was also thinking of getting one of those gear vendor overdrives, does anyone have any experience with those?
Dodge never put an overdrive behind a big block and no factory OD auto trans will bolt to a big block.

However, it is possible to mount a 518 to a big block with the proper adapter.
http://www.transmissioncenter.net/SwapInformation.htm
http://ramchargercentral.com/index.php/topic,108276.0.html
2490766410078436729S425x425Q85.jpg

2986953900078436729S425x425Q85.jpg

This is a 2wd, but a 4wd 518 can be adapted the same way.

I'm no Mopar nut, but isn't it possible add a the A518's O/D (seperate rear section) to a TF727 to make a hybrid? My brother has the TF727, and had an overdrive added internally somehow... I'm pretty sure that's what they did, but I'm not certain :-\ He upgraded to a push button torque converter lockup (A518's and TF727 didn't have a factory lockup), and it now has a push button for the O/D.
The Chrysler 518 is "basically" a 727 with an overdrive in the tailhousing. But you can not retrofit an overdrive tailhousing onto a 727. The main cases are different and have different oiling/hydraulic circuits.

I believe the '94-'96 46RH (same as a 518, Dodge just changed the naming system) did have a lock-up converter.
 
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oxbronco

Active Member
Thanks for the info. Im going to go with the 518 and adapter. Sometimes I think Im just about done with this project and then something else comes up. I have finally realized that it will never be done. Thanks again for the info.
 

Rot Box

Diesel and Dust
Location
Smithfield Utah
The Chrysler 518 is "basically" a 727 with an overdrive in the tailhousing. But you can not retrofit an overdrive tailhousing onto a 727. The main cases are different and have different oiling/hydraulic circuits.

I believe the '94-'96 46RH (same as a 518, Dodge just changed the naming system) did have a lock-up converter.

Interesting :cool: I guess my brother ended up with 100% 518 then. There is a lot of support for the 518 trans, and it seems to hold up pretty good even behind the diesels.

The 94-96 46RH did in fact have the factory lockup, and I believe thats the torque converter you use when converting the 518 to the lockup style. That being said you would have to use a toggle switch to engage 4th because there would be no "brain" or controller ;)
 

tv_larsen

Well-Known Member
Location
Logan, Utah
Interesting :cool: I guess my brother ended up with
The 94-96 46RH did in fact have the factory lockup, and I believe thats the torque converter you use when converting the 518 to the lockup style. That being said you would have to use a toggle switch to engage 4th because there would be no "brain" or controller ;)

The lock-up and non-lock-up converters use a different input shaft in the transmission and I'm sure the valve bodies differ. The trans input shaft differs because oil is supplied to the lock-up clutch through the center of the shaft and it also has different spline length.

Activating the lock-up with a manual switch isn't the only option. At the Transmission Center link I posted they use oil pressure and vacuum switches to automate over-drive and the lock-up.
#1. The center wire on the transmission is the hot wire and the two other wires are ground wires for overdrive and the lock-up torque converter. The front wire is the overdrive ground and the rear wire is the torque converter lock-up ground. You can get a three wire female connector from a junk yard or buy one from us.

#2. Run a 12 volt fused wire that turns on and off with the key to the vacuum switch, then to the center wire on the transmission connector. This is a normally open vacuum switch that takes 7 inches or more of vacuum to shift into overdrive and lock-up the torque converter and 3 inches or less of vacuum to down shift and unlock the torque converter. Lets say you're in overdrive going 54 miles per hour at very light throttle, when you press on the throttle and the vacuum drops below 3 inches the transmission will immediately shift back to 3rd gear low range without lock-up or even a lower gear depending on the throttle position.

#3. At the governor pressure tap on the transmission install a tee fitting for two oil pressure switches. Say a 44 PSI oil pressure switch for overdrive and a 52 PSI oil pressure switch for the torque converter lock-up. Or any other combination of switches you may want. At light throttle the transmission will shift into overdrive at 44 MPH and the torque converter will lock-up at 52 MPH. The pressure switches go on the outside of the transmission case in the governor pressure port. It's located on the right side, at the upper rear of the main transmission case. The figures on the pressure switch will only be correct if you have a stock tire size and rear end ratio.

#4. Run a wire from the front pin on the transmission connector to the 44 PSI oil pressure switch and a second wire from the rear pin on the transmission connector to the 52 PSI oil pressure switch. Now at 52 MPH when you step on the gas the transmission will shift back to third gear and the torque converter will unlock at the same time. It can't get any easier than this.

#5. Install a toggle switch in the overdrive ground wire. When the switch is turned off you will have 1st, 2nd and 3rd low range, exactly like a 727 transmission with the same ratios. When the switch is turned on you will have 1st, 2nd and 3rd gear low range plus 3rd high range. When the toggle switch is on the transmission will immediately shift into overdrive at light throttle over 44 miles per hour whenever it’s in drive range on the gear selector. Once in overdrive the transmission will not come out of overdrive until the overdrive solenoid is turned off, or the vehicle speed goes below 44 miles per hour, or the vacuum drops below 3 inches. The only electronic parts on a 518 transmission are the overdrive and torque converter lock-up solenoids.
http://www.transmissioncenter.net/SwapInformation.htm
 
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