4 speed auto in 89 d 250?

[tinaanddale]

I have a 89 250 with the factory auto trans ,I would like to replace it with a 4-speed auto. If so what year and what electric components are needed to complete the swap. Thanks, Dale

 

[rrausch]

You might call ATS just outside of Denver. They have done a number of 1st Gen's, replacing the trans with a 2nd gen trans. 800-949-6002

 

[1stgen4evr]

727 to 518 or later

The only requirement is to be able to turn on the overdrive. On the later trucks, that is under the control of the PCM. (Power Control Module) The PCM takes its inputs from the TPS (Throttle Position Sensor), temperature of the engine, temperature of the transmission, miles per hour, and maybe from the sensor on the rear axle. One or more of these factory controls will be sure to give trouble in short order. If you simply provide an on/off switch installed on the shift lever, you are in control of the od. There are post on the subject of changing the factory control to driver control with the switch on the lever.



You do not have a PCM or TPS on your truck. Be very glad.



The early second gen trannys have some improvments internally that are desireable. A first gen transmission that has been updated and with a better torque converter is quite good. Most transmission shops that are familiar with the Dodge needs can handle that.



Save the 727. They are in short supply. The transmission you have was only used on Dodge trucks for a few years. While there aren't that many looking for a 727, unless you change to an OD, you must find one "in the field".



I plan to do the same thing with my 89. Also the drive shaft is not the same.



1stgen4evr

James