I agree - since the mid-1970's conventional oils, changed in a timely fashion, have kept Toyota engines free of varnish, sludge and substantial wear for 400,000+ miles. Many thousands of members of the Toyota 400,000 mile club used conventional oil. Who has ever known or heard of a Toyota owner that experienced engine wear out of failure because they used conventional oil in the motor instead of synthetic?

 

Are you sure about that. You know why I know you are making hyperbolic claims as if you know the history of Toyota vehicles is because you don't know what is common knowledge.

Toyota is the manufacture out of all manufactures that was famous making sludge monsters from 1996-2002 for their most popular engines. The only reason why they were able get through this turbulent time period is a completely new engine design and the improvement of conventional oil standards.

Ironically the engines effected were some of the best Toyota engines ever made in terms of durability and the the owners found out the solution to the sludge problem was using synthetic oil and or oil flushes.

Toyota initially claimed that it was the owners fault for not changing the oil but the problem was so widely spread that there was a class action lawsuit that effected 3.5 million owners in the US. Eventually Toyota acknowledged that they were at fault and paid out the claims.

Even today I have seen sludged and varnished newer engines like the 1zzfe which was an oil consumer because the deposits are notorious for clogging the piston oil drain holes not to mention the clogging the VVT oil control valve screens.

Let me tell you that oil sludging continues today with a lot of Toyota engines to some degree so much so there is a website victims unit dedicated to it.

http://toyotasludge.com/

Video

 

I found an article written by CR that recommended using synthetic oil for sludge monsters. There are many other articles where they mention the use of synthetic oil for the cure but this one holds more weight if people still agreed with the old CR study.

http://www.consumerreports.org/cro/c...udge/index.htm

 

This is about as controversial subject as top tier fuels. lol

As far as CR, I wouldn't give a boot full of hornswoggle for their reports. IMO they have proven themselves anything but trustworthy many years ago, and that's when I quit subscribing and reading them. YMMV.

One other thing- I was pursuing a career in marketing many years ago. When I realized what they were teaching, and their blatant "techniques" for successful marketing (ie anything to get somebody to dump their wallet on the table), I shifted my focus elsewhere. Caveat emptor.

I for one, am favorable for synthetics, but for any reason except marketing drivel...

 

I wholeheartedly agree with you and I'm one of the biggest critic of CR because their word is taken as a source of fact when they have been wrong multiple times on their recommendations.
I had a subscription for over 15 years and canceled it because I have no need for knowing the best sun tan lotion.
The reason why I linked to CR rather then other articles that give validity to my point is mainly because some use CR as their only trusted reference and because they published a study long ago making a case that synthetic oil had no value over conventional oil which some people reference today despite the preponderance of evidence that modern synthetic oil has value.

 

I said conventional oil "changed in a timely fashion". A few Toyota engines over the years have had design deficiencies that made them more prone to form varnish and sludge. But 6 month / 5,000 mile oil changes were sufficient to keep the sludge prone 1997-2002 1MZ-FE V6 engine clean and running sweetly for hundreds of thousands of miles. The affected owners didn't need to spend extra money on synthetics, oil flushes or oil analysis. The bottom line is the vast majority of Toyota engines can stay clean inside and maintain like new cylinder compression figures on all cylinders for many hundreds of thousands of miles if the owner uses conventional oil and changes it in a timely fashion.

 

In many of those cases engine oil was changed in a timely fashion based on the manufactures recommendations and revised recommendations. It is well documented with receipts and Toyota dealership records with real people that were affected not with a little varnish but a complete engine failure. Toyota has come forward and not only admitted blame but also revised those engines. Many is not few and it was a class action law suit.

Do you have any links or documentation that prove your case then just hearsay.
I think I furnished enough of evidence that is contrary to yours but if you have sources for your claims I would like to see them.

 

Just to show you how much of a big deal it was here is another link.

http://www.consumeraffairs.com/news0...ettlement.html

Apparently it was estimated in 2007 to cost Toyota hundreds of millions of dollars. That's a big deal and not a little varnish and sludge.

Here is another quality link from a trusted source that recommends using synthetic oil to prevent the sludge condition with a comprehensive explanation.

http://www.toyoland.com/sludge.html

Please let me know if you need more links.

 

CR has been a great source of information for me, including tracking items of importance, such as the sludge issue. They certainly aren't infallible and shouldn't be the only source of information about a product, but I've found them to be invaluable over the years. As with any other source, one needs to separate (as best as possible) fact from opinion.

I consider their used car reliability surveys as one of the best sources for this type of information. As to CR's car reviews, those are far more subjective, although they were spot-on about the LS460 when it was introduced.

 

I agree it's not all bad but some people use CR as gospel and are closed off to other sources of good information.
Apparently in a 2005 CR article they concluded that the sludge problem was not due to infrequent oil changes.