Check engine light on - transmission problem?

The check engine light went on in my 2001 AWD Grand Caravan yesterday. My wife says it feels like the AT isn't shifting properly. I drove it around
the neighborhood and it felt fine, but now she says it only happens at highway speeds. She took it to autozone. They hooked it to the computer and say it is for a transmission problem, but it is nothing critical. Either they didn't give her the error code or she didn't hear it.
Anyone know what is going on here? Is it a major problem or what? Thanks.
Funny thing is that a month ago I put my 99 Explorer and 01 GC, both with 100,000 miles, up for sale; figuring I would keep whichever one didn't sell. The Explorer won on Saturday, so it is gone.
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The fault may not be critical now, but it could quickly become a show stopper if you don't take care of it. If you service your transmissions as recommended, then the repair should be minor. I have over 136,000 miles on a '98 Dodge Stratus V6 and the transmission is still working great. If you have never changed the fluids in your transmissions, then it may require a complete rebuild. This would be true for the Explorer as well, and it would likely cost much more to rebuild than the Caravan. I had a '98 Mustake and don't care much for Fords. Getting rid of the Explorer was probably a good thing.
Gyz
Toller wrote:

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