GM has a moly lube specifically for driveshaft splines, brought out when the C/K pickups developed a sticking issue. Most Chev dealers should have it.
Ford had the same issue with their Super Duty trucks and they have a special lube for it too that will work fine. Should be able to find it at any dealer.
Been a GM line tech for years and was using the GM stuff. Was at the GM training center in Burbank and they were recommending
488-1 Red Crown lube for slip yoke splines. Been using it ever since. The stuff is awesome.