Car Shudders When Stopping--2008 GP GXP V8
 

My GXP that I just bought shudders when stopping. At about 20 mph, the car shudders as though the transmission isn't shifting down--similar to the old Roto-Hydramatics when the linkage wasn't set right.

The problem goes away if I shift to neutral before stopping or if I enter the Slapshift mode so the car is in first gear when stopping.

Does anyone have suggestions on a fix--vacuum modulator, adjustment, etc.?

This was a common problem on some Mitsubishi cars when l/u converters were first used. The fix was to use ONLY Mitsu trans fluid in the trans.

TCC engage/disengage issue? Any codes present? Take it to someone that can plug in the scan tool and watch the switches in the trans, I'll bet it would be easy to see.