Howdy guys, I have and 86 f-250 with a 460 with a C6 that sometimes doesn't like to go into reverse. It'll always go eventually, but sometimes it takes like 30 seconds to finally drop in. It never does it going forward tho. I haven't changed the fluid/filter for a while, but it doesn't have many miles on it since the last one. Got me stumped. any ideas would be greatly aprikiated.