I've finally got my '86 244DL on the road after months of rehab work.

While taking it on it's first 20+ mile drive on the highway, it slipped out of OD after about 15min of driving (at night).
The "5" light was still on and when I let off the gas to a coast, the OD could be felt kicking back in and the RPM dropped, but the moment the gas was pressed, it acted as if it were in 4th.

I've already changed the fluid in the tranny and took out for another test and once that fluid got hot---OD disengaged back to 4th. Got about 15miles out of it. I have not checked the OD filter screens. Nor have I removed and inspected the OD solenoid.

After changing the tranny fluid I wiped down the back of the solenoid where the elect. contacts are and where it screws into the OD case.
Upon arriving back from test drive, I noticed that there was a tiny bit of fluid around the back of the solenoid where its case meets the inner part w/ the electrical contacts. Nothing anywhere else. I had noticed fluid there before, however, there was so much grime, I couldn't positively say that was the area. Now, I am sure as this time the fluid was brand new looking.

I've looked at the FAQ's for the M46 and think I know the problem, but I need something cleared up regarding the engagement/disengagement in the OD due to leaky O-rings: Can the O-rings in the solenoid cause OD to slip out? Should I just replace the o-rings and test again, or do I have to overhaul the solenoid and clean around the coil where I'm sure was completely full of fluid?

I'm hoping that it's not internal to the OD unit itself.
I had tested the solenoid at a previous time not long ago and it does exhibit a nice audible "click" when 12V is applied. I know my electricals are good as I can always get the solenoid to click when I sit in car and have tranny in 4th and hit button, having a friend underneath listening to solenoid.

I'm going to be going across the country in this car in a few weeks and hope I don't have to do it w/out OD.

Thanks.