Ringing around trying to get a sensible price for an oil change, one dealer asked me if I wanted semi-synthetic or synthetic oil. I hadn't a clue. What oil should it normally have?

In the end, I have it booked in for an oil change using fully synthetic oil with my local dealer for

I believe the difference between synthetic and fully synthetic is dependent on whether your vehicle is on variable or fixed service intervals (the latter being fully synthetic)...

For a quote of

Hi Bomski,

Can I just say what a Great Guide, I'm still on the look out for the right vRS in my price range, but have to say that ( being someone who knows nothing about cars) I think I'd even give doing an Oil Change a go!!!

Many thanks

MarkT.

The VRS has a PD engine, where the injectors operate at very high pressures, I would be very careful about using an oil which on its' data sheet does not mention the relevant VW standard, like the one mentioned above. VW Quantum PD oil is designed for that engine.

Synthetic oils last longer than semi's and mineral oils. Their chains are more resistanty to breaking down than their semi and mineral counterparts so will provide better protection for more of their life.

Fully synthetics are also known to remove more deposits from an engines internals than the other oils, thus keeping things a little cleaner but on old engines this can result in reduced compression where the deposits are sealing certain areas of the combustion chamber and also oil leaks where the gunk is helping to seal tired oil seals.

It's easier to get a fully synthetic to flow at lower temperatures which means you can get the oil to circulate faster round the engine when cold, thus improving cold start protection and fuel economy.

It's also easier to have an oil with a wider temperature/ viscosity range when it's fully synthetic as the chains are stronger. This means you can make a multigrade that's nice and runny when cold but doesn't turn to pi55 when hot.

Once an engine is fully run in, fully synthetic is an ideal choice due to it's enhanced properties. The only thing is it does cost more to use.

Also, I wouldn't recommend changing to it on high mileage engines due to the points mentioned above. If the engine has been run on semi or mineral for most of its life and is now above say 100k, I wouldn't change to a fully synth to be honest. Most of the wear on the engine will have occured already and also the chances of springing a leak etc are higher.

VAG Spec 505.01.

That's what matters.

Full or Semi Synth is of secondary importance.

From this page...

http://www.briskoda.net/forums/fabia/what-engine-oil-should-i-use-my-fabia-vrs/23797/

This oil...Millers XFE-PD SAE 5W-40 (semi-synthetic)

Can be had from here....

ASP TRADING MILLERS

For

If you run your car in the Briskoda way you would never need to top it up

VW / Skoda require the oil to meet VAG Spec 505.01

However this requires the oil to be tested by VW at great expense to the oil company. Hence why Millers XFE-PD SAE 5W-40 (semi-synthetic) is pretty expensive stuff. Also i bet they can't then market this same oil for the Merc or BMW without re-branding it to remove the PD or VW references!!

Millers do a better fully synthetic oil (can't remember the code) for only slightly higher cost as they do not have to recover the cost of passing VAG 505.01. When my car's 3yrs 60k i'll be swapping to this as recommended by my mechanic/millers.

I believe the difference between synthetic and fully synthetic is dependent on whether your vehicle is on variable or fixed service intervals (the latter being fully synthetic)...

For a quote of