Quote Originally Posted by Russ Myers View Post
My comments come from being an auto mechanic for over 35 years. Quaker State and to a slightly lesser extent, Pennzoil, will sludge up in an engine faster that you can imagine. the oil in question will break down under high heat and pressure faster than any other oil. I have no imperical data on this finding, no hard facts, just years of working on customer's engines. Yes, I know other oils will do this when not changed properly, it's just that I've scooped "Q" out with a spoon from engines that I have all the records on.

Russ
A few quick comments: Good call that these are actually the same company... Or at least I assume you knew based on lumping them together...

More importantly: I am curious, were these customers all using synthetic oils? That's what we are talking about here. Any experience with conventional counterparts does not apply here IMHO.

Racing engines do not usually develop engine sludge. They see totally different operation cycles than street engines. Even IF these oils are more prone to sludge, it doesn't really matter here...

That said, oil is like religion... As we've already seen in this thread, there are many different beliefs out there and many people who have had different experiences or upbringings who believe very differently, but strongly about oil.

I believe in any brand name synthetic and change it often. I do not pay extra for Royal Purple or Amsoil. We happen to be running, the oil in question, Q Power (20/50) in our Nissan. We've been very happy with it so far and these "truck" engines are not known for being nice to oil.

I also believe that most of the fancy things they brag about is marketing and you have to look at the "tests" they do very carefully...