iv got a 91.6 with the A518 trans and when i get in it in the morning my OD works fine but as soon as the truck is warm it wont work i have tried just about every thing but the manual switch its been doing this for about 2 or 3 monthes

 

There is a temp sensor in the trans line near the front of the trans that might be bad.

 

i tried to jump the coolant switch ant what i thought was the trans temp switch but i wasnt sure is the trans switch on the driver side

 

I dont think jumping the coolant temp switch will do much for that. The trans temp sensor is in the trans line under the truck near the bell housing of the trans on the driver side. Kinda near the shift linkage. Unplug the sensor and short the two wires together and see if the problem goes away. If if does replace the sensor and if it does not change it is in the trans.