Contrary to most transmission problems, my 722.32 tranny only has a problem when it has been driven six or seven miles or so and is at operating temp. When it is cold and just starting out and for the first five miles, it shifts and functions perfectly. ATF, filter change less than 10k miles ago. This is a used trans and I still have the other one, although it was used as well. I have the valve body out and am ready to do a thorough cleaning. Going to have to use the old gaskets as I can't find any without buying the whole rebuild kit (costs more than a used trans.) The problem when it is hot : slips out of top gear for no apparent reason; very difficult to get back into gear and then usually in third and from there, it has a mi8nd of its own--quite a scary chore getting back home; I have tried the "easy" adjustments (cable and vacuum adjustments) to no avail. Any suggestions ?

Sounds as if you are ready for a rebuild. As the fluid warms it gets thinner and you'll have less pressure. With worn clutchpacks this drop in pressure is not enough to hold the clutch pack engaged. The more you drive it in this condition, the more likely you will increase the cost of the rebuild.

Sounds like you are losing hydraulic pressure within the transmission hence causing the slips.Your seals might be going or some of the valves might be sticking sometimes.

How many miles?

Do you have the right recommended atf in the tranny?

__________________
1986 300SDL, 211K,Dealership serviced its whole life
1991 190E 2.6(120k)
1983 300D(300k)
1977 300D(211k)