Odd shifting

I've got a '94 V6 with an auto tranny and the other day I was driving home and it just didn't seem to be shifting right. I was just following the flow of traffic at a consistent speed, the transmission wanted to down shift as if I hit the gas, but I didn't. It also hesitated when it went to shift a couple times. It would rev up to about 2500, from about 1500, and take a few seconds before it would shift.

Also, when I hit the highway, it would drop out of overdrive, similar to what it did in the city.

Any ideas as to why its doing it and how I can fix it.

I would first have the codes run

Then i would look into the MLPS or VSS sensor going bad.

Also might want to check the fluid level, same thing happend to my cavalier, but it just got low on fluid. Thats the 1st thing id check.

I know its not fluid related, cuz the levels are fine. I do plan on changing the filter and replacing the fluid in the not to distant future.

I've also done some checking on other forums and it sounds like a speed sensor issue. My only question is where do I find it? Is it something easily accessable or is it something that requires some major work to get at?