Warming up 300TD transmission question
 

I have been researching about my shifting probs for a few days. While driving I have figured out that the car (1981 300TD Wagon 250k+) drives great and shifts fine for the first few minutes of driving. after a few miles, slipping and flaring and not being in the right gear at the right time. tranny fluid is not burned or smelly. i keep getting weird (smeared) dipstick readings though so i dont know if there is too much or too little or neither...Tomorrow vac modulator test and all that stuff...I am going to have a local shop do it the first time.

So anyone experienced shifting problems only after the tranny is warmed up and is this a tell-tall sign of anything.

Thanks