Oil change every 5k miles or 3 months?

I used Royal Purple full synthetic on my last change. The oil looks like it has an odd purple color when you pour it in but it actually clear, it only looks purple going in because the bottle is purple. Could that be the case with the green Syntec?

 

To follow up a bit on jayman's helpful information about EU quality oil, the ACEA A5 specification is more stringent on certain aspects of oil properties than the A1 specification. That is why it can be used for extended service. For example, the A5 oil must stay in viscosity grade for the shear stability test, but the A1 oil can thin and fall out of grade 30 minimum cSt at 100 C. A5 oil must also be much more resistant to viscosity increase than A1 oil. The Noack volatility must be less for the oil to meet the A5 specification also.

Another specification that people can possibly look for is GM 4718M, which is good enough to go in a Corvette.

I looked up some of the more popular 5W-30 synthetic oils, all of which meet GM4718M:

Mobil1 is A1 but NOT A5
Castrol is A1 and A5
Amsoil ASL is A1(I guess, it wasn't listed) and A5
Pennzoil is A1 and A5

 

I recently had my 5,000 mile service done. Gave them Mobil 1 and asked them to use 42/40 in my tires.

Has anyone else noticed a change in their energy monitor after their first check up? It seems that the ICE is running more than before and that my mileage may have dropped a bit.

I used to be able to run off of the battery at low speeds farily easy.. not it doesn't seem to be the case.

Thanks

 

<div class='quotetop'>QUOTE(Truffles @ Apr 3 2006, 02:33 PM) [snapback]234318[/snapback]</div>

Mine dropped too, but it went up again. It seems to do that with every change.

 

<div class='quotetop'>QUOTE(sub3marathonman @ Mar 5 2006, 09:17 PM) [snapback]220914[/snapback]</div>

The oil in Europe is tainted with "food for oil" scandal. :angry:

 

<div class='quotetop'>QUOTE(Dr Rocket @ Apr 4 2006, 09:19 PM) [snapback]235029[/snapback]</div>

Like the oil companies here aren't?