Your serial number indicates the year 1987.
Your Marlin model 336CS(Carbine Sporter)was made in the year 1987.
Your Marlin model 336cs(Carbine Sporter) was made in the year 1989,with the serial number that you have provided.
Your serial number indicates that your Marlin model 336cs was made in the year 1995.
1988
1988.
1996.
1990
1983
I would say that your Marlin model 336cs(standard carbine) was made in 1983.
your marlin model 336 was made in 1985.
I can say that your Marlin model 336CS was made in the year 1984.I would look to Marlin,s own website to get any more info on your model of Marlin lever action rifle.
1995.