Hey i just got a 1994 c2500 with a 4.3 and 4l80e trans with 77k miles for free. Guy said it had no fluid on the dipstick. I put about 2 quarts of valvoline dex/merc in it(i know it should optimally be dexron VI but its what i had laying around) So driving it, truck does not shift into 2nd 70% of the time, feels like a neutral until you floor it. I may have overfilled the trans. Would this be a reason as to why theres no 2nd? Also first time I checked it i believe there might have been a little bit of water on the dipstick.