2000 Caravan 3L V6 transmission

:angry: I have a 2000 Dodge Caravan 3L V6 and lately it’s been acting weird. Yea. I bought it shiny new off the lot and up to now it’s been right as rain. But.. it is 13 years old and is cresting the 200,000 km mark on the odometer. I’ve checked the transmission fluid and it’s fine,(even though I haven’t felt any lurching or slippage). Over the past few months, it’s periodically been in the habit of trying to race into high gear even though I’m in town and only doing around 35-40 KPH, because it simply does not want to go up to 50 KPH when it starts giving me attitude. When it’s doing this, the tach is usually sitting right around the 4000 RPM mark. (Usually between 1500 and 2000 RPMS inner city at 50KPH). Once I park it, let the engine cool down, it’s fine until it warms up again. I’ve spoken to a few pretty decent backyard mechanics and get different possible answers. Dirty or faulty speed sensor? Timing belt? Low fluid? (I know I said I checked that, but I’m not sure it was accurate as I don’t have a level spot on my driveway or that I let it idle long enough to get warm) If anyone could give me insight or has had this problem and found out what it was, I would love to know where to start to get this fixed. The van is in good shape otherwise and I would like to keep it on the road awhile longer.