Someone across the Atlantic needs help with the transmission in his 66 Mustang with a 289 and a C4.
He has to give a lot of gas to make his car move and it feels like if the brakes are on and sounds like a horn from an antique car. The reverse works with no problem and when he disconnects the vacuum hose from the transmission, the noise disappears and the car moves perfectly in first gear.
The oil and filter have been replaced but it didn't fix the problem.
Would it be related to a clutch band?