Well, I am not sure if this has been discussed on here before but I feel the need to warn everyone here that about 8-10 months ago the EPA stepped in and had the oil manufactures change up their formulas on motor oil and remove the Zinc as the new cars do not require it.....our trucks do require it and running the new oil in our trucks will cause cam failure in new motors....this applies to all flat tappet cams.....there are a couple of manufactures Valvolene VR1 and SHELL ROTELLA that still have the Zinc additives but who knows for how long.......apparently Uncle Sam did not see any need to publicly announce this to anyone running older cars but GM has a memo that tells their service people to put an additive in older cars with flat tappet camshafts.....sorry to drag this on but I had the need to vent......I found out the hard way when my newly rebuilt 350 wiped the cam at all of 11,000 miles in my stock 72.......if this has already been posted then I think there should be a sticky somewhere to let everyone know.....
Thanks