[W126 Coupe] Hard shift cause and cure

[Chet Hwilka]

.... However, the fluid was quite cloudy or foamy.
Coolant in the transmission fluid.
Time for a new radiator....

Check the fluid level with the trans at operation temp. (it will register
10mm lower when cold) 
I believe I read somewhere, that if the fluid level is too high the trans
will churn up the fluid (like a blender) and cause it to be foamy..

Chet