Toyota Repair: 97 toyota corolla, toyota corolla, reputable shop

Question
driving car today & it starting making noise like something was rubbing or dragging.  Once on highway it got louder, car very briefly slowed down then picked up speed again, however, speedometer was no longer working; it stayed on 0.  I was told that this indicates the transmission slipping. Is this correct?  I was told to drain and re-fill (not flush) transmission fluid and add something called LUCUS to it.  He said this would correct the problem and stop the transmission from slipping.  Is this correct?

Answer
Danielle,
This is impossible to diagnose by e-mail. Take the vehicle to
a small reputable shop. They won't charge much to diagnose it.
I don't know if its a engine or transmission
problem. If your transmission is slipping that would be the correct
procedure to try.

Tim