1987 automatic sometimes freewheels when manually going from fourth to third, no rhyme or reason for it, I have to rev the motor up to road speed and then it will engauge.
I do not think it is a sprag problem, just not sure how the thing works.
Fluid is clean and fresh, possible sticking valve body?

The trans shifts great, the fluid has never smelt burnt or any thing like that, not really worried about it as I have spares and a Euro 5 speed to install in it.

 

Call Steve,
1-845-576-0312

 

B2 piston is sluggish to engage. B2 stays engaged from upshifts 1-2, 2-3, so when downshifting 4-3, B2 re-engages. Probably a stuck valve in the valve body. VB cleaning is probably in order.

 

I will do a flush on it and use some BG stuff in it and if that does not take car of it I will go ahead and do VB.