Th400 no third no reverse
It would seem that the Direct clutch assembly is not holding or not applying.
The question is why NOT...
What have you checked/ inspected/ looked at thus far?
Was the fluid level full?
How does the fluid look? ...Burnt, clutch debris, metal debris ???
What are the line pressure readings?
Do you know which valve-body is being used (which manufacturer and which model) ?
If not, do you know what modifications were required to install the valve-body?
Let us know...
Once you provide some meaningful information; we can try and deduce as to why the direct clutch assembly is not operating as it should.
Or if something else is wrong/ causing problems.
Good Luck!








