Synthetic Oil in Trailblazer 302

[SundownIII]

I suspect that Lincoln is being cautious with their oil recommendations, especially regarding break-in.

Most manufacturers caution against using synthetics during the break-in period. Internal parts need to wear in or seat. Often times, this doesn't happen when the engine is started off on synthetics.

After the break-in period, I think it's been proven that the synthetics have their advantages.

[davedarragh]

Synthetic vs Conventional Oil

The major difference between Synthetics and "regular" oil is in the molecular structure. Conventional oils, refined and distilled from crude, have an uneven molecular structure, and have limits regarding hi and low temps.

Due to this "uneven" molecular structure, conventional oils are best suited during the "break in" of engines. Minor irregularities in castings and machining promulgate the use of conventional lubricants "filling the gaps."

In extremely low temps, conventional oils form sludge, and at high temps, the chemistry of the oil can break down into sulphurs, waxes, and promoting pollutants.

Synthetic oil, on the other hand, has a near perfect molecular structure, as it's produced chemically. These oils have been tested to -62F with no change in viscosity. Oil temps have been monitored as high as 400F without breakdown in chemistry.

The major drawback, is the price of synthetics. It can be a trade off of "insurance" for prolonging the life of an engine, once "broken in."

Those of us who are old enough to remember "Lithium Grease," have seen the extremely hazardous material, "Lithium Hydroxide Monohydrate" virtually disapear from the industry.

The largest stockpile of this material was once stored at DOE's High Assay Uranium Enrichment Plant, near Portsmouth, Ohio. Once used as a catalyst in weapons grade Uranium, was all sold to grease (Nat'l Grease, Kansas City) and battery manufacturers (Union Carbide) in the mid 70's, about the time Mobil was perfecting synthetic oils.

It was a very caustic material and an extremely high respiratory irritant.

[Corbinworks]

I have always used RedLine in my bikes & Quads but when I am not using syn oil I use rotella...I still have 11 hr's b4 my first oil change on my 302..What are you guys using for filters?

[shortarc]

I have always used RedLine in my bikes & Quads but when I am not using syn oil I use rotella...I still have 11 hr's b4 my first oil change on my 302..What are you guys using for filters?

Mine has 1500 hrs. on it with nothing but Mobil one after break in. I use Wix filters the # is 51394. Just thought to add mine has the Subaru engine on it. Might not be the right # for Kohler.

[Corbinworks]

Might not be the right # for Kohler.

yeah thats the motor mine has..

[Miller John]

Great conversation guys. Use the same viscocity synthetic oil as the manufacturer recommends for standard oil after break in. It is recommended to run 100-200 hours wth conventional oil to break in the engine. Synthetic oil is great for small engines. If you want your engine to last a long time, stay away from Ethanol based fuels as well.

[Sberry]

I got a couple engines I am going to run synth in, going to see if I can make the season with single change. One doesn't get that many hours, called for 30 wt and with dino nothing but that seemed to work right, had hi temp oil pressure drop but the 5-40 synth seems to be working and is really noticeable at low temp starts. I had been changing it to a multi dino for winter, hours and loads were low as were temps but its a pain, looks like the synth is going to work and the savings in a couple filters minus a whole change,, and service when busy may pay. Just put it in Kohler lawn mower too, gonna go for 250 hrs or so before I even think about it again. Been trying it in some golf carts too, they really get pounded here, over heat, over load, etc. Might be able to make those on 2 changes or so a year. I had been changing about once a month when they work hard.
Might cost more but last longer and in some equipment reduce the need for change just due to seasonal temps.