***The Engine Oil Bible***

[ilikerice]

And that for it can Hold your Engine compression ratio if you chose wisely.
Why do you think if they do a Engine compression test and put small amount
of oil on the top of the piston the Engine compression raise up.

Think of that!

You check compression as is. If you have low compression in a cylinder, then you put a small amount of oil in the cylinder to try and seal off your piston rings. If you still have low compression you are just ruling out that your piston rings are good.. Then you look for other problems like bent valves or head gasket.

My opinion on all this after doing many 3.0L desludges from ES300 and RX300, Just read your owners manual and go by thier scheduled services and the oil they recommend. I personally will use any full synthetic that is on sale that month with filter. 99% of the time sludge happens when people use conventional oil and skip out on thier expected oil changes.