Much of todays NEW stuff is just refreshed and re-marketed old stuff many times with the same ingredients just a more modern "scientific" name. Like Denny, I read a lot and have also sent off to get the "tests" results(and how they were done) that they offer on the back of the bottles. Well, I'll be damned, the little difference they rave about is about as worthless as ....well you know. And how the tests are set up leaves one to wonder.
I've sent off for a bunch of them and while there is SOME MINUTE truth to what they claim it is solely to take your money and down right almost negligible.
I'm one that has said you can't restore an engine out of a bottle. Additives may "prolong" the eventual end but its mainly to get your money.
I do also believe that some of the stuff is good......for different things so each has to be evaluated on its on merit.
Example: my lifters are shot on my silverado after 218,000. They click/clack every morning for a few seconds. Well, I did put a little Lucas in it but I don't think it helped a bit. The lifters are shot and no bottle gonna fix them. So, I'll drive it till it dies and pull the engine. Hey, this stuff is mechanical and it WILL wear out.
Denny, my personal thoughts on the ZDDP is be careful. I have seen two newly rebuilt V8's with flat tappets go sour due to this problem and have read several reports on this. Those two engines were from very reputable shops in town and who have been in the engine business for years.
IF it was mine I'd definitely put me a quart of E.O.S. (engine oil supplement) from the local Chevy dealer. Better safe than sorry.
