chevy silverado 1996 V8 5.7L has white smoke?

white smoke is antifreeze in the oil, you either have a small crack in the block or your head gasket is worn out, or "blown".

if the white smoke begins as soon as you start the engine its probably not antifreez leaking from cracked block,as the motor heats up would cause the crack to expand enough to leak,so it could be a head gasket.have a mechanic pressure up ypur radiator after the motor has warmed up so the thermostat is open,see if the pressure drops that would indicate a leak,or it could be the addative has a petroleum base and that would produce some smoke for a while. read the lable on the can see what it containes and then go from there

I don't like the white smoke thing. But without more info I can't give you a definitive answer. Does the smoke disappear after it is warmed up? Like condensation in the exhaust system ? Most common problem if the smoke is there all the time is an internal coolant leak, like head gasket or a crack in the head etc.

To be honest, I am not 100%

Smoking weed selling coke .

It is normal if the white smoke doesnt continue to come out.

However, the problem may be caused by coolant or water coming out from the tail pipe because of overflow of coolant or leakage of water pipe.

I would have done a prebuy to check this truck before you by it.That way no surprises.That could be trouble but without a checkup it's
only a guess.