Posted by: Mark Polk | 2013

71 Power Wagon Finding a Transmission

I have mentioned several times already that one of my major goals with this build is to reduce the high RPM’s thus saving some money on fuel. The truck is going to be a driver more than a show truck. I already replaced the gear sets in the front and rear axles to 3.55 which will help significantly. The other piece to the puzzle is a transmission that will help to lower the RPMs.

I have had a formal eductaion on old mopar transmissions over the past several months, to say the very least. After talking to a transmission shop owner we determined Ishould try to find a hydraulic lock-up 727 transmission for the truck. What this means is at highway speeds a valve opens and the torque converter locks-up dropping the RPM’s. Dodge equipped many 727s with this feature from 1978 through 1988. The problem is locating a core to have rebuilt.

Old transmission cores are getting more difficult to find, especially rare ones. I have searched for months and still don’t have one. If I don’t locate a core soon I might be forced to use a non-lock up 3-speed 727.

Update: I have wasted months looking for a lock-up 727. I have scoured junkyards from NC to SC to VA with no luck. This was really holding up the build so I had the transmission shop rebuild a non-lock up 727. It’s no exactly what I wanted, but these 727 transmission are durable and will work well when I tow the vintage travel trailer to shows with the truck.

Join me in my next post when the real work begins

Mark Polk

Auto Education 101



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