Q: I have a ford expedition and accidentally drove it in 2nd gear on highway over 45mph for about 5minutes any damage to the tranny?

Hi Brandon. In an older vehicle like your 2000 Ford Expedition, inner transmission seals and gaskets are fairly worn in general. Driving in second gear in an automatic transmission up to speeds of 45 could have possibly damaged inner components - especially if you’re having issues shifting into reverse. However, it’s also possible that the shift solenoid is damaged. I think before you attempt any repairs, it might be best to have a professional mechanic come to your location and complete an onsite inspection so they can determine the source of this issue.