Does anyones Diesel oil run golden?


Registered User

I recently bought a Diesel A4.

The oil in the engine was like crude oil which I quickly replaced with 5/40 fully syn + filter.
Although I poured in golden oil it was instantly black and mucky on checking the dip stick..

3 weeks + 1000 miles later I have just done another oil change.

I instantly checked the dip stick and it was golden until I drove the car and its black again.

Have I so much crud in the engine that I need to do a few changes to run golden or being a Diesel engine it just will never run golden!?



Well-Known Member
VCDS Map User
it always goes black in the diesels
iv noticed it aswell


VCDS Map User
Welcome to diesel's!

They will only ever run golden when new, or maybe after an extensive rebuild.

We had a customer bring a Yaris back as it had no oil in. It had plenty, but was new, so was still golden.


Yorkshire & Humber Rep.
Regional Rep
VCDS Map User
The reason why diesel oil goes black quicker than petrol engines is due to its cleansing properties. It cleans an lubricates the engine, similar to what v-power fuel will do for the fuel system.

I ran some of this on my old car as a flushing/cleansing oil before putting the good stuff in, plus it was a little thicker and quietened down my noisy tappets :)

@udi A3

Well-Known Member
VCDS Map User
8 oil changes to make the oil run golden?! MADNESS!
Generally you can feel the clean oil in a desel after a change, but they all go black right away, had a few cusomers complain we hadnt actually changed there oil after services when i worked in a garage. We always offered to change it again in front of them but they would have to pay again when we proved this to be the case!


the oil is doing its job. just because it has changed colour does not mean it has lost its properties.
I can put in honey syrup colour oil into my audi a3 2.0 tfsi and even after a good oil flush and extra oil change it will go darker within 100 miles. Not a bad thing. I had it lab tested and it was still good oil... no problems with thermal flash point, no excess acids/break down etc.


Looking for Boost!
Staff member
Goes black almost immediately after you start it up, sounds normal to me.