Very Black Oil At 7,500Km Change...

[FPV6T]

when I have had my oil changed at ford(only because my mate is the manager there and I know it gets done properly!),they use valvoline 15w/40w.it gets done every 7500km.

[82CNT]

That puts my theroy to rest hahahahaha. If its good enough for mazda turbos its good enough for mine.

[Gloo]

I think it also has a lot to do with the service history of the car. My old ba had 40k on the clock when I bought it, it took 25k of 5k services untill the oil was baiscly the same colour it went it. The car had previously only had ford spec 15k ones done. 15k is way to long, but in regards to oil. I dont think it really matters what you use as long as its within specs and you do it often. Maintinance is the key.

[dashturbo]

If the oil goes black, I isn't it doing a damn fine job.

Its collecting the carbon deposits on the cylinder walls. that's why I change mine earlier than 15k, to collect and dispose of the contaminates.

If the other brands of oil are not going black, I would think they ain't collecting the contaminants like they should, the detergents aren't doing their job.

Cheaper oils will breakdown and can't maintain their viscosity at higher temperatures, particularly if the oil gets hot. Sythetics generally hold their viscosity characteristics longer.

my dealer uses Halvoline? god knows what its like, I use penrite.

Edited 09/03/10 01:16 AM by dashturbo