80000 miles. Car starts moving normally but shifts quickly through the gears bang - bang - bang until trying to shift into overdrive at about 25 mph. It shifts quickly weather I am applying full throttle or taking it easy. It then slips and will simply over rev until it gets to speed which takes a fair amount of time due to the slippage. It doesn't seem to be slipping once to speed but I can't really tell either if it really locks in. However if I apply full throttle at highway speed it does rev up and slip.
Transmission slippage on 1990 Lincoln Town Car
Check the TV cable at the throttle body and see if the grommet has broken. This is what tells the transmission how much throttle you are giving. If it breaks, the pressures in the transmission default very high. If you do not replace the grommet early and quickly before driving it too much, permanent internal damage will occur. Very cheap part causes very expensive damage.
1 more answer
your just spinning out the clutches. the pump seals are bad. need an overhall to fix the pump seals