Chevrolet Repair: 95 chev pu 5.0 auto od 150K will not shift, transmission repair, chev

Question
if i wind out 1st & let off the gas it just goes into neutral. fluid is a little burnt, thought i'd change fluid & filter, but I've never seen that fix a Trans once they start acting up. truck belongs to a friends 16 yr old son, he has been driving it about 2 weeks.

Answer
Hey,

 I hate to tell you this but something is burnt up int he transmission as 2cnd gear or 3rd won't hold.  It might be time to take it to a transmission repair facility and have it scanned for trouble codes to see what the clutch index is.

WAyne