More oil changes using regular oil = Using synthetic oil?

[Ricky1]

OK, I am sort of safe at home from you fantastic Forum Members to dare to suggest the following: Why not use regular oil and just change it more often than use synthetic oil?

I have a newly acquired 2005 CS that is out of warranty. Yes, I am a CS rookie.

Will not using synthetic oil screw up the variable valve timing thing? ( I assume that its Porsche's version of Honda's VTEC )

I would think not using synthetic oil would void warranty... if you had warranty.

Actually, I haven't found any place in the manual that indicates which oil to use. I am just guessing synthetic (Mobile 1 maybe... a Mercedes recommendation for a E320)

What would screw up if I don't use synthetic oil?

So far I have driven this monster of a SUV "sparingly"... I don't think I've gone past 2800 rpm. This also brings up the question of just using regular gas vs premium high octane as recommended. If I am not driving this vehicle "hard", I don't need premium gas, right? OK, compression ratio is high = 11.5:1. So pre-ignition with low octane gas would damage the engine. But I am not driving this suv hard at all and there is a knock sensor right? And if I am not reving the engine up... thus advancing the timing/cam shaft, thus igniting the fuel/air mixture earlier in the power stroke... then I don't need premium gas, right?

Its getting late and I am just rambling on... regular oil and regular gas... what do you think? (Its a serious question with a bit of fun mixed in).

[JFP in PA]

OK, I am sort of safe at home from you fantastic Forum Members to dare to suggest the following: Why not use regular oil and just change it more often than use synthetic oil?

I have a newly acquired 2005 CS that is out of warranty. Yes, I am a CS rookie.

Will not using synthetic oil screw up the variable valve timing thing? ( I assume that its Porsche's version of Honda's VTEC )

I would think not using synthetic oil would void warranty... if you had warranty.

Actually, I haven't found any place in the manual that indicates which oil to use. I am just guessing synthetic (Mobile 1 maybe... a Mercedes recommendation for a E320)

What would screw up if I don't use synthetic oil?

So far I have driven this monster of a SUV "sparingly"... I don't think I've gone past 2800 rpm. This also brings up the question of just using regular gas vs premium high octane as recommended. If I am not driving this vehicle "hard", I don't need premium gas, right? OK, compression ratio is high = 11.5:1. So pre-ignition with low octane gas would damage the engine. But I am not driving this suv hard at all and there is a knock sensor right? And if I am not reving the engine up... thus advancing the timing/cam shaft, thus igniting the fuel/air mixture earlier in the power stroke... then I don't need premium gas, right?

Its getting late and I am just rambling on... regular oil and regular gas... what do you think? (Its a serious question with a bit of fun mixed in).

You should not be using anything but a full synthetic oil in the car. Full synthetics are a different animal than conventional oils; they have lower surface tension, better heat transfer, and much superior film strengths than conventional analogs. They also utilize totally different additive packages and have much longer running lives before they fall out of grade. Using a non synthetic is false economy, you will pay for it in the long run. As for what brands and weight, that is always a topic of conversation, but there is a published list of Porsche approved oils in the document archives.

[clarksongli]

i agree with JFP:

1. Synthetics as mentioned are a good comparison to dino's.....although if you aren't careful, many synthetics are using dino bases.

2. Synthetics have much better lubrication properties when comparing similar viscosity oil.

With that said, i change my SYNTHETIC M1 oil every 5-7k miles.....oil is cheap insurance compared to the price of a Cayenne. IMO, although oils have come a long way, contaminants remain an issue, so fresh oil is never a bad thing.

As for gas....our cars do have knock control for sub par gas.....but again, why bother? We bought Cayenne's, not an bronco....Even with knock control, i would still be concerned with possible knock and premature issues related to that.

Bottom line.....Good fluids, frequent changes, rated fuels

[wvicary]

Also keep in mind not all synthetics are created equal. You also have to consider ash content and many other factors. Just stick with a recommended oil and you'll be safe.