How fast diesel oil gets dirty?

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Here is my problem:
When I visited my parents during Christmas time, my dad told me about the problems is having with his car. I will do a different thread for that.

During the conversation, we obviously opened the hood to look at the oil level: It was already a quarter low (don't know what amount the mark on the dipstick represents, but full sump is about 4 liters), but more important, the oil was tar black, even more than when I changed my oil after 6 months/ 7500 miles.

The problem is that two months earlier, and 2000 kms (1250 miles) ago, he supposedly had an oil change at the dealership (annual change). Is that normal for the oil to be so black already?
I went to two quick lube stores and asked them what they thought of that, but one told me that there was a problem and to change the oil right away, and the other told me that it was normal for the oil to be black already, so that did not help me much.

The car is a Citroen Xsara, the Picasso (minivan style) version, with an 1.6 turbo diesel engine, the 110 HP version (more boost than the 90HP version from what I understand). About 120.000 kms now (75.000 miles), doing about 10.000 miles a year (about 7.000 highway miles and 3.000 miles really short trip errands). Oil is changed annually and there is usually one quarter left on the dipstick with no top off. I told him to top it off regularly than just watching the level going down.

Do you think they really did an oil change and that the fact that the oil is already black is normal, or do you think they only did a top-off (not even reaching full)?

How is the oil color 2 months after an oil change in your diesel engine?
 
I agree with everyone -Diesel oil get dark very rapidly.It may be possible to have a shop or parts store to test the oil's TBN to determine if the oil was drained as claimed.
 
Originally Posted By: Pesca
Is that normal for the oil to be so black already?

Absolutely. Jet-black is 100% normal for a diesel.

Originally Posted By: Pesca
How is the oil color 2 months after an oil change in your diesel engine?

As dark as the Ace of Spades printed with India Ink on a surface of pure bitumen tar on a new moon night... exactly the same it was immediately after turning the key with a sump of fresh oil.
 
IME, it depends on the engine, perhaps due to EGR implementation. The old Ford 6.9 IDIs we had in our fleet wouldn't ever completely blacken their oil. On the other hand, the GM diesels from just a few years later would look like an inkwell after just a few minutes.
 
Originally Posted By: motor_oil_madman
My oil will be black by the time I get to the end of the driveway. (75ft)


+1, before that.
 
Originally Posted By: JHZR2
Originally Posted By: motor_oil_madman
My oil will be black by the time I get to the end of the driveway. (75ft)

+1, before that.

+2, I owned a 1981 Volkswagen Rabbit Diesel many years ago and for the longest, I thought there was something wrong with the engine. The oil would turn black within a day of an oil change. But this is totally normal on a diesel engine.
 
BJ42 Landcruiser with 3B engine, and you could see a dirty swirl on the dipstick on a fresh fill.

Nissan Navara ZD30 takes 3,000km until you can see it decently on the dipstick.
 
Originally Posted By: 2010_FX4
Originally Posted By: JHZR2
Originally Posted By: motor_oil_madman
My oil will be black by the time I get to the end of the driveway. (75ft)

+1, before that.

+2, I owned a 1981 Volkswagen Rabbit Diesel many years ago and for the longest, I thought there was something wrong with the engine. The oil would turn black within a day of an oil change. But this is totally normal on a diesel engine.


That is basically what the second mechanic told me: "Just moving the car out of the oil change bay, you would think I did not change your oil".
The first mechanic was a little bit too anger to get my business in the way he was behaving.

Thanks a lot everybody for the quick answer, that puts me at ease.
I will soon do another thread about my dad's engine problem, once again soliciting your expertise.

Thanks.
 
What kind of fuel mileage (kilometer-age?) does that Citroen get? That's the kind of car we need down here in the US-a TDI that can actually carry 4 full-sized adults in comfort. BTW, the Ford 6.0 in my sig is the only diesel I've seen that doesn't turn the oil black instantly.
 
Originally Posted By: bullwinkle
What kind of fuel mileage (kilometer-age?) does that Citroen get? That's the kind of car we need down here in the US-a TDI that can actually carry 4 full-sized adults in comfort. BTW, the Ford 6.0 in my sig is the only diesel I've seen that doesn't turn the oil black instantly.


He usually gets about 5,7 LHK ( a little more than 41 mpg) combined doing a lot of short trips and some long highway runs (80-87 mph for about 3 hours). He freaks out when he gets more than 6 LHK, LOL!

He got it because it is very useful, a lot of cargo space to bring back cases and cases of wine (in his own words), but from outside, the newer version is less ugly. His looks like an egg on wheels.

Problem is I am not sure people over here would buy lots of them: The engine is only 110 HP, and that is the most powerful diesel option for that car. As long as people don't change their mind they NEED at least 200 HP, they won't get a lot of success.
 
Nothing wrong with a 110bhp turbo-diesel. My TDI has a whopping 90...
grin2.gif
 
On my 5.9 cummins, rotella is black with <100 miles. Pennzoil long life looked almost new at 250 miles. This was through 3 oil changes, so I went back to rotella. No UOAs to suggest something was wrong, I just didn't think it was normal NOT to be cleaning. That was 3-4 years ago, and LLG may be different now.
 
Originally Posted By: motor_oil_madman
My oil will be black by the time I get to the end of the driveway. (75ft)


Pretty much the same when I had my TDI. It's normal for a diesel's oil to get black fast. Don't lose sleep over it.
 
Oil getting black quickly in a diesel, especially emissions equipped, is par for the course. But is not always true.

I disabled the emissions on my '06 Cummins ISX, and the oil stays almost fresh from the bottle clean for at least the first 7,000 miles. I presently have 25,000 on my oil and it is just now getting dark like within the first couple of hundred miles when it had emissions junk working. At normal 30,000 mile average oil changes, my soot is at .1 ppm.

The oil getting black is not a problem. These newer diesels have higher soot concentrations thanx to EGR. Most of the soot is small enough to not cause any real damage, and latest oil formulations handle soot bonding better to keep from forming larger particles that will do damage. But the total concentration can only be determined by UOA.
 
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