Hi, If you havent allready come to the conclusion that the trans needs an overhaul and had it repaired,,,, Here's the reason why....The lip seals in the clutch packs and servos are by now very old and hard, SO..when the trans oil is cold the clutch pistons and servos hold the pressure due to the cold haevy oil,,NOW.. when the oil get's hot,,,You guessed it....SLIP CITY....Info from a retired trans tech....GOOD LUCK... Clay..