the whole tcw-3 thing seems to have created a lot of confusion in oils, but the tcw rating refers to lubricity, (meaning how slick or the lubricating properties of the oil).
a lot of oils may pass the 3 rating, but if your going to compare walmart to oem oil you'd find they both pass tcw3 fine, but the detergent package along with several other additives contained in a good oil such as brp,yamaha & merc. are present where in cheap oils they are not.
76gmc1500's post is a perfect example, no wear because the lube is there, but carbon build up is greatly reduced with a good oil.
and true motor manufactures dont make oil, but brp has a set of specs that there oil is made to. i think citgo is still making it for brp, and its not the oil that makes oem oil so expensive as much as the additives,
theres an old saying "you get what you pay for" which is especially true with oil.
and yes im sure the profit margin with oem oils is a little higher than other brands but its still a much better quality oil in the long run.
as for synthetics there great in air cooled, hard working, or newer motors that run at higher temps.and especially the occasional overheat, as ther flash point is higher than reg oil. meaning the oil dosent burn off at higher temps. but remains to provide lubrication.
JIM
|