If the solenoid or pressure sensor is going south, it won't care if it's cold or hot.

Either way it will shift poorly in gears 1 - 3.

 

where would said sensor be located? i called the local parts guy and all he could find is a speed sensor.

 

You have to remove the tranny pan and then remove the filter. It's right behind the trans filter.

Here's one of my DIY's for that sensor and solenoid.

Just scroll down to transmission and drivetrain, it's the first hyperlink.

http://www.doghousediesel.com/id13.html