Thank you for your reply. Yes. I did think of that and when I was driving down the road I noticed two things. It 'seems like' when I am going slow, then accelaerate in one 'click' or push of the button it appears to accelerate quicker. Then after slowing abit, clicking again, it appears that it does not have the same acceleration power. But honestly, I am just not too sure. I live in Providence and getting good speed is for any time period is difficult, even on the the highway.
The Thunderbird is very clean and seems to be well kept. I did call the previous owner and he said he never used the button so would not know. He seems honest, but then again, he sold a car to me. so..... other than this concern, I must say it is one of the best cars I have ever had. This is the first used car I ever boutht, and always wanted a Thunderbird!!! So far I am pleased.
Ok. Additional information now that I think of your question. In attempting to watch the shifts, when it hit 65-70 during acceleration from about 40 mph, it seemed to get heavy and not go any faster for a few seconds, and then kick in again, but did not feel like it was 'slipping' so I feel ok, so far. I am not sure I can tell how many gears it is going though.