I'm relatively new to old trucks and I could use a little bit of help with this. So I bought this truck from a guy about two weeks ago. It has some cosmetic issues (which isn't why I'm making this) but recently I've noticed that when I'm in second gear (it's a 4-speed manual) it surges incredibly high even when I'm only going 15-20 mph. Is this common? Or is there an issue with it? Also, an unrelated note, when I'm driving in third gear sometimes the stick will actually pop itself out of gear and I'll have to shift it back in and hold it there so it doesn't pop out. Why is it doing this? And is there a way to fix it?