Okay so my kid decided to borrow my truck. It's older and has a few problems one of which is the shifter does not change on the dash it always looks as if it's in park. You have to feel it out to put in drive. Well Its spilled oil all over now bc he drove in I believe second gear for about 10 miles. What kind of damage am I looking at? I'm thinking it's probably a gasket. And how much will it cost to fix?
I would check the trans fluid level and engine oil level. It is possible that the tranny fluid got hot and bubbled out the vent. If the fluid level is low I would just add some to get it to the correct level. At this point any damage is already done. If the tranny is shifting ok, but fluid has a strong burnt smell it may be worth flushing and replacing it. The engine may have used some oil just from the high revs from being in second gear.