quote:Originally posted by wylchyl:
I have been in the automobile business for almost 40 years and have found that pcv system has lots to do with sludge..if the crankcase is not ventilated properly, then moisture can build in the engine helping to create sludge. And as another post said, the extended oil changes don't help especially when most drivers just run a few blocks around town at a time never allowing the oil to properly heat and evaporate the moisture
This is probably the most sensible thing I have heard in a while,and very,very true.
This is exactly the reason why I use Synthetic oil that has the lowest possible NOACK volatility numbers.
Many of today's cars don't even have a PCV-valve that can be replaced because the system is now sort of integrated. Imagine clogging that type of system up!
I have found that highly volatile lubes(quickie lube),are used with poor quality gasoline, has become a recipe for disaster in many cases,if not all.
If motorists would only run synthetic Motor oil with a volatility(NOACK) of 4-7%, run top tier gas,and do a few freeway runs on occasion,there would be a lot less sludge out there,if any.
This not only will keep the engine clean,but keep it "like new" for as long as possible,which in turn......keeps it clean for as long as possible. It's a very healthy pattern.
Once the bad pattern(varnish/sludge-wear-varnish/sludge-wear/occurs).......it's rebuild time. So it's best to avoid bad patterns in the first place.
Even when True synthetic does evaporate in very hot weather/climates and sees long hard engine runs over the longer haul,and many,many thousands of miles, it seems to only lay down a very thin non-varnish type of "pure" oil film that is harmless and doesn't clog or coat/layer up.