Dodge Repair: 90 dodge spirit: A604 trans problem

Question
I has dodge spirit 3.0 when you start car and put it in to drive it will go up to about 5 mph then goes in to neutral put car in park shut off restart and will do same thing first time it went in to neutral was with no warning while driving down highway have tried shift solenoid and tcm with no change another issue that started at same time do not know if related is tach is not working properly goes up when rev up but will not come back down also tran will not go in to reverse also started at same time
Thanks
Art

Answer
Hi Art,
First check the fluid level on the trans dipstick, and if needed us Mopar type 7176.
Then get a fault code readout from the transmission control module via the blue data link connector that is located under dash the fuse box. It requires an OBD-code reader such as that made by Snap-on or the Chrysler DRB-II for the early 90's time frame. Be sure that the readout is via that plug and that it is for the transmission fault codes which are 2-digit numbers. They could be confused with fault codes for the engine which are also 2-digit but are accessed by a plug in the engine compartment. Once we have a fault code we can get an idea of what is wrong. Ask the shop what the code means, what are the possible causes and how they would approach the repair. Then we'll compare notes.
Roland