No full throttle 1-2 shift


New Member
May 25, 2001
I have a th400 in my T-type and it will not shift out of first at full throttle. It was just rebuilt and has a vigilante torque converter. It will shift if I cruise normal or let off the throttle.
Presuming that this is not a manual valve body,

how are you supplying a proper signal to your vacuum modulator?
Will not work...

Unless you have a one way valve in it. Boost is going into line. It will never shift. Either one way valve it or go to a manual vb as it cures permanantly:)