Contour Enthusiasts Group Archives Forums Modifications Zetec Maintenance Synthetic oil???

So my car has had synthetic oil since 100,000kms it now has 158000kms and after 8000kms the oil is coming out a lot darker than when it goes in.To my knowledge after 8000kms it should come out looking pretty close to the same as when it went in.Conventional oil will change color a lot after like 3,4000 kms but synthetic is a lot different. Does anybody know what this could be caused by or has anyone had has similar problems.Obviously if i'm running a little hot or if my breather is getting contaminated it's going to affect the oil but to me my oil seems a little to dirty for the amount of kms i put on between each change. I will have the oil tested but if you guys have any input let me now please.soory for the long post.

I work at Wal-Mart's Tire and Lube, and I can't say that I've ever seen a car - synthetic oil or not - that the oil wasn't black. We have quite a few vehicles that run Mobil 1, and when they come back it's always black as can be. I'd say that you shouldn't be too terribly worried.

Sounds like the detergent part of your oil is doing its job.
The reason to change oil is not because the oil is used up , its because of the dirt and contamination circulating in the oil.

Very true the oil will change color but after dicussing the oil with my partner here at work and my elevator tech both of which are auto mechanics as well said that synthetic oil shouldn't change a whole lot unless it's the first couple of times you put it in the car after using conventional oil.mobile 1 rocks anyhow but now I have two different opinions and I agree with you. Well I guess I'll just have to get it tested to be sure.

Mine changes colour also
'95 190000 km
'97 110000 km

A color change can come too if you just swapped brands but have been with the same one for a long time. Compare, say, Mobil 1 to RedLine. The Mobil and the RedLine will have different additive packages. One will protect differently then the other, one will also clean differently. If you have been with one and just switched, you could be cleaning something in the engine that wasnt cleaned before.

Originally posted by fasti4contour:

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Well the oil loses it's viscosity and therefore will not coat the parts very well and yes contamination.But there really shouldn't be that much contamination unless the engine is getting fuel past the piston rings.But some yes is fine.sorry to sound anal but I love my contour to death and can't stand it when she doesn't run good

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The viscosity doesnt change that quick. My last change was pulled out at 6000 miles, the viscosity was still dead center at a 30w (210 degrees). The killer is the acids that the normal conbustion process creates. These deplete the bases in the oil. Thats what will wear out faster, the Royal Purple that I used last only had about 1500 miles of life in it.

The fuel/water that does get in the oil will vaporize under normal (read: fully warm) conditions).

If you are worried about it, send away for a oil sample kit. They will be able to tell you if all is good Clicky!

My Mobil 1 Test, if your curious. I have yet to upload my RP test.

8000 km is too long of an interval. According to my Pennzoil training at their tech facility the interval should never exceed 5000km. The oil is darker, always will be, because of all the contamination from metals, combustion, unspent fuel and detergent action. Synthetic is only meant to provide extra protection in severe duty environments like every day driving, or extreme cold and hot. I once lost all coolant in a turbo engine and the synthetic cooled and lubricated at hignway speed.

Not sure what km=in miles, but I know you can go over 5k miles on almost any oil, whether synthetic or not. And I know that's more than 5k km. It just depends on how good your engine is and what conditions it sees. People have done real tests and you can go a suprisingly long amount of time, especially on synthetic with a good engine. My mobil1 doesn't change color much at all after 3k miles and I have no qualms about going 5k miles or more. I just change it when I feel the urge and it's always pretty clean it when I change it.

True, if driven under the perfect conditions the new GMs with the oil life monitor might not see their change oil light for over a year or 15000 miles.

I call BS on that one, especially if the owner uses crappy oil.