trans slipping questions

From : polxcsp

Q: my 97 4x4 360 auto ram sport with 64k mi had a strange thing happen today..i traveled 12miles to a store shut off truck for 10 min then on my return trip i noticed my as soon as i pulled out of the store the truck was slipping between shifts including od so once i got on a long road i took off od and increased throttle only to have a severe slip 5000 rpm going 30 mph on a flat road..i thought i was haveing a major failure so i drove about a mile very slowly till i came to a traffic lightonce green truck was shifting normal and believe me i tried to make it slip in 3rd and od but problem vanished..when i got home i checked fluid level - ok color was reddish-ok i think and no smell..ive had this truck since 1999 at 30 k mi and never noticed this..before i get my truck looked at id like any suggestions and advice that may save me from some major repair i might not need... thanks for any help with this problem... kevin 97 360 sportbest truck ive ever owned .