I have a 95 Eldorado and it won't shift past 60 mph could it be a shift sensor
Could be. Take it in and have the transmission mechanics check it out.
suspect vacuum to the vacuum modulator has fallen off, changing the shift points radically.
1995---bout ripe for rubber to start degrading..probably a full replacement of all butyl rubber with synthetic nitrile rubber would be advisable if you want a few more decades of service out of them~