Classic/Antique Car Repair: 64 tbird convertible, manual lever, shift lever

Question
QUESTION: hello brad. when i eccellerate from a standing start my 64 t'bird appears to be in second gear!if i select first it starts as required.it never seems to change back.hope you can help thanks shane

ANSWER: Does the transmission up shift through the rest of the gears?

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QUESTION: Yes it changes up no problem!It just never changes back to low

Answer
There is a one way clutch inside the transmission that engages low gear when the shift lever is in drive. This one way clutch is over ridden by the hydraulic system when the shift lever is in low, explaining why you have low gear when the manual lever is moved to low. The transmission will have to come out and apart.
Brad