My 94 Bronco has about 120K miles on it. Never abused. For the past 10,000 miles the tranny kicks out of gear after traveling 10-15 miles. It usually happens between 2nd and third and 3rd and OD. It will kick out of gear then drop back in if i let off hte gas. Has this happened to anybody? Is it my converter or is it something more serious? Fluid levels are fine. Also sometimes it will go two three days without doing this. PLease help me!