In Reply to: Re: gummed up Volvo posted by Jim on 08/02/02 at 2:12 PM:
Sorry, but you are not on the mark this time.
I know the components of both oils. I think you missed the point entirely. The vis is not the problem. The problem is simple. Chemical reaction between the two oils.
The oil put in without my permission is not compatible with the PAO synthetic ester based oil I use. A reaction can and is often immediate. This is due to the presence of metal catalysts, temperatures of up to 220f in the engine and hundreds more degrees in the turbo up to (900f).
I founded this forum for the purpose of informing anyone who wants to know - oil is not just oil. Oil is base stocks and additives. There are four categories of base stocks that cover a wide range of chemistry (even in each category). As for additives, there may be thousands.
Oils advertised as synthetics are not all synthetics. Severely hydrotreated oils, severely refined oils and some oils with poor chemistry for the job are all allowed by the oil industry to be called synthetic oils. (The number of actual synthetic manufacturers is 1/5 of all the manufacturers claiming to make synthetics)
Unfortunately for auto, industrial, commercial and marine, many failures are caused by mixing "synthetics". This happens in engines, gear boxes, electric motors, bearings etc.
The oil that caused the problem is not a bad oil. It is a highly refined and hydro treated product with different additives than the oil I use. It is also known to cause such problems when mixed with other synthetics and off the shelf additives.