Jungle Jim, if you read the thread about the sludge engine you will see that some people don't like Penzoil either. My friend said the oil is from the same area and the same type of oil as Quaker State and it tends not to hold up. Then if you read more of the thread you see some people defending Penzoil. I remember Consumer Report doing a test and saying all the oil they tested seemed to hold up the same. My feeling is that changing the oil often is most important.
Here is a quote from BOB IS THE OIL GUY at that site on that thread:
--------------------
" Toyota is the ONLY engine that has those gears on the heads. As Gman pointed out, those gears are notorious for shearing down a normal oil in viscosity. We have evidence that in the normal v6 sludge engines, a 30wt oil(castrol gtx) will shear down from a 30wt to a 20wt just inside of 3500 miles confirmed with oil analysis and no evidence of any contaminants. There is also evidence that shows anyone that did 3k drains did not in-fact have any sludge issues. There is also evidence that only certain engines had this problem and most times it was ones that had tight engine compartments, where air flow was lacking and had smaller oil sump capacities. "
--------------------
As you can see he is slamming the oil I like, Castrol GTX. He also doesn't like Toyota engines much either. He also mentions that people that change their oil at 3,000 miles do not have sludge problems. Just more to think about.....
__________________
2001 & 2004 Toyota 4Runner SR5 4X2
Both V6 and both Natural White
"Yeah, I like white and I like 4Runners"