For several months my van randomly drops into a lower gear or won’t
shift to the next gear.  I then pull off the road & cut it off for a
minute or so & start again.  This seems to fix it until the next time.
I drive by myself often is this the start of something bigger?
Sometimes the service engine light comes on & sometimes is doesn’t.
The mechanics said that they have to look at it when its doing it to
know what is going on!  Any
ideas?  Has anyone else experienced this?