Happens in my wagon since I've owned it (5 years). Usually only happens after sitting over night regardless of the weather that night. Probably not your transmission but have the fluid and filters changed anyway. The recommended interval for our car is 30,000 miles. It should shift very smoothly almost with the 'manual transmission' hesitation between gears when you jump on it like I do. Some on this site think it si the oil pump warming up. Good luck with the new ride - you'll love it. Do searches on wiring harness, OVP, kick down relays, throttle actuators and fan clutches to know what to expect in the near future.
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