[this guy]

Hi all,

When I bought my car 12 months ago I was told by the seller that it has just been serviced, and after my initial test drive I checked the oil and it was clear, which was good.  Recently I had the car at the dealer for its 30,000km/24 month service. Being as sceptical as I am, I checked the oil when I got home and the oil on the dipstick was black/blackish. I would have thought that fresh after a service and a mere ~9km trip home, the oil would not have had an opportunity to turn black so quickly, especially considering that after my test drive 12 months ago, the oil remained clear. I also checked underneath the car a few minutes ago and the plastic cover on the undercarriage shows no signs of removal, having dirt/dust all over it. On a positive note though, the oil filter cap does have signs of manipulation.

Is it normal for oil to change colour so quickly? Or should I be questioning the dealer? I wouldn't think that they would fail to change the oil since any problems that could arise from that would fall back on them via warranty claims, but I can't help but treat the dealer with a great deal of scepticism - minimum effort, maximum profit.

[Phil №❶]

The crdi engine has an EGR valve which allows some sooty exhaust to be reintroduced into the combustion chamber to facilitate cooling of the air fuel mixture. This is a normal function and the result is that there is some contamination of new oil. Don't worry as long as you change the oil at the recommended schedule all will be well.

[liability]

I found that my fresh oil will go black very quickly, its just a diesel thing.  Also, remember that there will still be some old black oil in the engine which will help turn the new oil black.

Some dealers use a vacuum pump and suck the oil out through the dipstick tube, so there is no need for them to remove the plastic cover under the sump.