Mineral Vs Synthetic Oil???

[WhiteGTB]

Heya all, just got my first service after my engine rebuild (12,500km).

I brought along my own oil, Castro Full Synthetic 5w-30 and asked them to used this.

After the service they said they replaced the oil with the one I provided but recommended it still run Mineral Oil until the next service.

Nevertheless Castro is now running in my engine and the engine is purring along nicely.

Does anyone know why they recommend Mineral Oil?

[Roddez]

Does anyone know why they recommend Mineral Oil?

Based on my experience in the Aviation Industry, we run newly overhauled engines on a different oil (Red Band) until the run in is complete.

The oil not only lubricates the engine, but it also carries things away from the engine as it is bedding in. These particles remain in suspension in the oil until it is changed, or if the particles are big enough they will be removed in the oil filter.

This is one of the reasons why people sometimes change the oil during the running in period. (50 hourly changes in Aircraft engines).

The mineral oils are better are storing these particles than the fully synthetic oils.

[MY05WAGON]

The two subaru dealerships i've used around here run mobil synth 10w-40 (part mineral and synthetic). They probably get a good deal from mobil for it. I've never actually done 12500k's between services so mine is based on time. I do however drop the oil in between dealer services, every 3 months or so. probably wasting $$$ but i do feel better.
I just go with the flow and use whatever they use or recommened, you would think they know best but thats probably not always the case.

Mik

[stuntgirl]

Does anyone know why they recommend Mineral Oil?

Based on my experience in the Aviation Industry, we run newly overhauled engines on a different oil (Red Band) until the run in is complete.

The oil not only lubricates the engine, but it also carries things away from the engine as it is bedding in. These particles remain in suspension in the oil until it is changed, or if the particles are big enough they will be removed in the oil filter.

This is one of the reasons why people sometimes change the oil during the running in period. (50 hourly changes in Aircraft engines).

The mineral oils are better are storing these particles than the fully synthetic oils.

correct.... i changed to synthetic in my liberty after the first 3000km so as to remove any metal burrs that float around the engine....