Oil type/changes

[tone]

Just wondering is changing the oil every so often ( as in between services ) a must or not really that necessary? Considering the car isn't driven grandma-like and isn't 100% standard.

When it comes to choosing an oil are their any recommendations from people on which to buy.

I've heard the brand Royal Purple being thrown around. and some number following eg Royal purple W10 or something like that. what do these numbers refer to?

Thanks for any help

Tone

[Doc]

I run 5w30. mobil one. Drop it every 5k..

I use to run royal purple, but now i get Mobil one for free.. so i just dump it at 5k

a 10w40 imo is a better oil for this car. And that is what I was running with the royal P.

The first figure is the viscosity when the oil is cold. So it flows like a SAE 10 would when cold. However when it get hotter it thickens up. and when at 100 deg C it flows like a SAE 40 oil would flow.

Multi-grade motor oils (ie 10w-40) perform well not being too thick at cold start up to prevent engine wear by providing more instantaneous oil flow to your donk. However, there is a draw back. These additives shear back in high heat or during high shear force operation and break down causing some sludging. What's worse is once the additive begins to be depleted the motor oil no long resists thinning so now you have a thinner motor oil at 100 degrees. Your 10W-40 motor oil can easily become a 10W-30 or even a SAE 20 (10W-20) motor oil. I don't have to tell you why that is bad.

Hence run the 10W-40.. and it may be a 30 in the end.. but the protection is there.

I have seen a bad report from royal purple after 8k. But I have seen a few good ones too.

Pensoil platinum seems to get a good wrap too..

[EQ]

Penrite 5W-40 was recommended to me, I drop it every 5000 too - I must admit that oils confuse me...

Would a car in Sydeny use different oil to me in Brisbane for example?

[Doc]

No.

I would only use a 0w oil if it were parked outside in under -10deg C all the time

A 5w is like water when its cold.

I may consider a 10w-50 or 15w-50 if i were beating the p!ss out of it around a track every few weeks though

Just my 2c though

Doc

[mav2777]

I use Shell Helix Ultra fully synthetic 10W-40. The oil changing intervals says 10,000km in the manual, but have noticed most change their oil every 5,000km & so I asked alot of questions amongst the people in the know. I rang Shell technical, then spoke to Mazda service & then a mazda performance shop & they all say 10k is sufficient for a fully synthetic oil.

[Doc]

I use Shell Helix Ultra fully synthetic 10W-40. The oil changing intervals says 10,000km in the manual, but have noticed most change their oil every 5,000km & so I asked alot of questions amongst the people in the know. I rang Shell technical, then spoke to Mazda service & then a mazda performance shop & they all say 10k is sufficient for a fully synthetic oil.

Well take a sample at say 8k. Send it for analysis, then youll have a real answer..

[Wardski]

I run 0W-40 Castrol Edge Sport and drop it every 4000-5000km. No problems with this oil, and its one of the better to take heat away from the cylinder heads. The level never seems to drop between changes (and I get no smoke), so its obviously not leaking past the turbo seals or eating much thru the combustion chamber.

The friendly chemists next door to my office at Caltex swear on this oil with their lives, for cars like ours.

---------- Post added at 01:49 PM ---------- Previous post was at 01:37 PM ----------

Well take a sample at say 8k. Send it for analysis, then youll have a real answer..

Theres not much wrong with going to 10,000km for stock standard cars. I recommend 5000km changes as you get quite a large amount of carbon buildup in the oil at around that stage. Your oil filter does take the majority of the carbon particles out of the oil, but some still gets thru. Not only that, but the carbon in the oil will reduce the flow rate thru the filter, and may increase the engine temps marginally due to restricted flow.

If you had an SP23, Maxx or Neo, I'd say yep, 10,000km is fine. MPS's, WRX's, Evo's - anything turbo charged, drop every 5,000km

[mav2777]

I am up for an oil change very soon at 50,000km. I will get an oil analysis done just to make sure if every 10,000km is fine for me.
Motor Oil Myths and Facts
This is a good article about oil changing intervals, myths & facts.

[Doc]

myths and facts are blown away by analysis.

Fact:

Our tiny turbo is pushed pretty hard stock.. it get veeery hot..it kills the oil

[Wardski]

myths and facts are blown away by analysis.

Fact:

Our tiny turbo is pushed pretty hard stock.. it get veeery hot..it kills the oil

Couldnt agree with you more Doc.