2000 Toyota Corolla TRANSMISSION problem question

I have an automatic Toyota Corolla and may be in jeapordy with losing my transmission. It isn’t making any bad sounds from the engine…but i’m dropping on the highway from 65 to 60 for no reason. What are other symptoms that it may be going?? Even if it’s not loud (the engine) is the transmission going, you think? How do i check my transmission fluid or can a mechanic only check that? Thanks!

I believe we are talking about a automatic transmission right? Yes you can check the fluid yourself. After confirming the fluid level is good and is not burnt I will ask you about transmission maintiance any? How is it shifting? hard and harsh or lazy and slipping(neither are good)Do you still have a owners manual? it will point out the Transmission dipstick location and fluid type.Let us know how far you get on fluid checking and post back more info (mileage)