The oil thread

[alexnoe]

How much does a thorough oil analysis cost compared to just changing the oil?

-Uwe-

In my area, the ADAC offers an oil analysis at 99€. At that price, you go there, they take a sample, send it to a lab, and you will get the analysis by e-mail. They don't specify how much of that is actual lab cost. However, the large majority of drivers wouldn't want to take the sample themselves anyway. If you want to take a sample on your own, I have found offers around 60€ for the analysis (+shipping to the lab).

My last service + oil change bill was 196€ for base work time*, they charged 5.5 x 25.13€/l = 138.22€ for oil, and 37€ for parts in connection with the oil change. There is 19% of VAT on top of these numbers. The bill does not spell out how much of these 196€ was working hours for inspection, and how much of it was working hours for oil change. If I wanted to buy the oil on Amazon, I could get 5 liters of VW 50700 0W30 at around 90€ or 5W30 at 50€. Now if you don't have a 2 liter diesel engine, but something a little smaller, you won't need 5.5 liters. I'm living in a very expensive area of Germany, so the same work order in a cheaper area would have cost around the same for oil and parts, but less for work time. Also, my car is a leasing car, so I need to go to a Škoda contractor. That's cheaper than a VW or Audi contractor, but more expensive than an independent auto repair shop.

Long story short: If you are technically interested in the result, do an oil analysis. But if you try to minimize the cost of an oil change, have no leasing car, and not a big diesel engine that needs something like VW 50700 0W30, it's probably not worth it.


* "non-base" work time would be additional work outside of the 2y/30,000 km interval, for example, the oil in the haldex clutch needs to be changed after 2 years or 60,000 km (56€ working hours + 64,86€ oil + 9€ for minor stuff like screws), and there is more of that. My first service was after 22 months, and I asked them to do everything that would be required after 24 months as well.

 

[Adam]

Ceratec is probably quite popular in Europe. How about Militec-1? Anyone uses it in their vehicles?
One of my use cases: I am adding it every time my Air Conditioning is being serviced (adding it to the AC's oil).
I've done a couple of tests (with Militec-1 and without it) and when the additive is present in the oil, the air temperature from the air vents (at the lowest possible setting) can be 2 degrees C lower (or even a bit more, IIRC), compared to AC system without Militec-1.

 

[Uwe]

Militec-1.

Wait, you're using a firearms lubricant in your A/C system?

Militec-1 Lubricant-Grease for Firearms-Autos-Sportsmen

Get information on typical use of Militec-1 Impregnated Lubricant and Grease and links to order products from our online store.

www.militec-1.com

-Uwe-

 

[Adam]

Wait, you're using a firearms lubricant in your A/C system?

Militec-1 Lubricant-Grease for Firearms-Autos-Sportsmen

Get information on typical use of Militec-1 Impregnated Lubricant and Grease and links to order products from our online store.

www.militec-1.com

-Uwe-

Apparently, yes For many years. However, here in Europe the bottle looks a bit different.
Not advertising anything. Just providing their EU website as a reference: http://www.militec.sk/#about

 

[bluetoes591]

As a former R56 Mini Cooper S owner, the choice is change your oil every 7000km, and your timing chain every 100,000km or change your oil every 20,000km like Mini says and then replace your timing chain every 40-50,000km because they simply do not last without oil changes. The N14 is an extreme case, but in all these modern turbocharged engines with timing chains, you are stressing the oil to a significant degree.

 

[alexnoe]

In my area, the ADAC offers an oil analysis at 99€....

I went to this ADAC station because I wanted an engine power test anyway, so I had them do both: engine power test for 159€ (came out with 155-157 kW between 3600 and 4600 rpm with HVO fuel), and oil analysis for 99€.

After 19.000 km, most oil parameters (iron, chromium, aluminium, tin, nickel, copper, lead, manganese, silicon, potassium, sodium, bismuth; viscosity) are fine, but my oil contains 8% of diesel fuel. Depending on whom you ask, the limit for diesel fuel in engine oil is usually put around 10%, and much lower for gasoline. It's not like your engine will break instantly if you use oil with 11% of diesel fuel, but it's supposed to be below that in the long term. In other words, it's not completely insane to go 30.000 km in my case, but based on this result, changing it after 15.000 km is defendable (=cautious, but not paranoid).

This result, especially the percentage of diesel fuel, is not completely surprising, because this engine is optimized for lower NOx production and higher soot production, so the DPF regenerates more often than in ealier engines. This is by design, so there is nothing wrong with the engine, but it is something that you need to keep in mind when assessing the oil.

 

[NZDubNurd]

Something else people don't think about - the volume of oil in the engine.

People on forums etc start spouting off about 5K or 10k oil changes etc...

I have owned a Subaru 2.5 4 cylinder, which held 4 litres and a 2.5 BMW 6 cylinder that held 7 litres. So 10,000kms in the Subaru is a bit like 17,500kms in the BMW, as far as capacity of the oil to absorb contaminants.

The BMW service indicator (calculates fuel used to determine servicing intervals) recommended about 22,000kms generally. It was serviced like that up to around 100,000kms, then I reduced the litres of fuel between services, so we ended up with 15-17,000kms with our type of driving. It was clean as a whistle inside, when I had the rocker cover off.

My first Subaru (1992 model) just used mineral oil at 10,000km intervals and "only" did a touch under 475000kms before it was de-registered and never burnt any oil - even though it had the arse thrashed off it by myself and the service manager at work . I don't know what happened to it, but that was it's last inspection mileage: I only had it up to 425000kms, when I left the job and they sold it not long afterwards.

 

[The WolfMan]

I went to this ADAC station because I wanted an engine power test anyway, so I had them do both: engine power test for 159€ (came out with 155-157 kW between 3600 and 4600 rpm with HVO fuel), and oil analysis for 99€.

After 19.000 km, most oil parameters (iron, chromium, aluminium, tin, nickel, copper, lead, manganese, silicon, potassium, sodium, bismuth; viscosity) are fine, but my oil contains 8% of diesel fuel. Depending on whom you ask, the limit for diesel fuel in engine oil is usually put around 10%, and much lower for gasoline. It's not like your engine will break instantly if you use oil with 11% of diesel fuel, but it's supposed to be below that in the long term. In other words, it's not completely insane to go 30.000 km in my case, but based on this result, changing it after 15.000 km is defendable (=cautious, but not paranoid).

This result, especially the percentage of diesel fuel, is not completely surprising, because this engine is optimized for lower NOx production and higher soot production, so the DPF regenerates more often than in ealier engines. This is by design, so there is nothing wrong with the engine, but it is something that you need to keep in mind when assessing the oil.

I think that diesel can act as a lubricant. Not a very good one, but it has some lubricant properties. Injection pumps in diesel cars need to be lubricated and the lubricant used is the fluid that they are pumping. Petrol in the other hand doesn't have lubricant properties. In fact, petrol is a very good solvent. also expensive. When someone puts petrol in a diesel car, the injection pump will not get proper lubrication and there is high risk of metal shavings in the system due to poor lubrication.

Volkswagen AG deals with this by replacing the injection pump, injectors and filters. Pipes can be cleaned...

A race car has only the required oil capacity for the purpose. A bigger oil capacity requires more volume and leads to more weight. Weight is bad. The cooling system only has the necessary openings/area. Excessive openings for cooling increases drag which leads to reduced top speed. If any of you watch Formula 1, for sure that you know that teams have different aero packages for different tracks and even weather conditions. Sometimes weather is hotter than expected and more cooling needs to be added to the car.

On the contrary, mass production cars have a big "safety coefficients". In your example, more that 10% of diesel in the oil it's not recommended, but maybe the red line is at the 20% mark.

In your case, after 19k km, how many km left to service the car says?

Something else people don't think about - the volume of oil in the engine.

People on forums etc start spouting off about 5K or 10k oil changes etc...

I have owned a Subaru 2.5 4 cylinder, which held 4 litres and a 2.5 BMW 6 cylinder that held 7 litres. So 10,000kms in the Subaru is a bit like 17,500kms in the BMW, as far as capacity of the oil to absorb contaminants.

The BMW service indicator (calculates fuel used to determine servicing intervals) recommended about 22,000kms generally. It was serviced like that up to around 100,000kms, then I reduced the litres of fuel between services, so we ended up with 15-17,000kms with our type of driving. It was clean as a whistle inside, when I had the rocker cover off.

My first Subaru (1992 model) just used mineral oil at 10,000km intervals and "only" did a touch under 475000kms before it was de-registered and never burnt any oil - even though it had the arse thrashed off it by myself and the service manager at work . I don't know what happened to it, but that was it's last inspection mileage: I only had it up to 425000kms, when I left the job and they sold it not long afterwards.

A fully synthetic oil is superior to a mineral one. I don't know how things are in America or in New Zealand. Here in Europe, I don't know who uses still mineral oil in their cars... In online shops, the difference in price between mineral and fully synthetic oils is so small (at least in my opinion) that I don't see any good reason to use mineral oil.

And I think that you can't do your math like that. Oil contaminants circulate in the oil and are retained in the oil filter when they pass through it.

The BMW has more journals, bearings and two more cylinders. More metal parts were the oil must "stick to" in order to avoid metal to metal contact.

 

[davisev5225]

Petrol in the other hand doesn't have lubricant properties. In fact, petrol is a very good solvent. also expensive. When someone puts petrol in a diesel car, the injection pump will not get proper lubrication and there is high risk of metal shavings in the system due to poor lubrication.

This is one of the primary reasons why ethanol is used as a significant additive in gasoline blends - lubrication of the fuel pump(s) and injectors.

Nope, I should have double-checked my info before posting.

 

[alexnoe]

In your case, after 19k km, how many km left to service the car says?

It tells me that I have 11k left for both oil change and service. Remaining distance to oil change and remaining distance to service are two different things in my car.

 

[Uwe]

This is one of the primary reasons why ethanol is used as a significant additive in gasoline blends - lubrication of the fuel pump(s) and injectors.

Huh? How does ethanol help with the lubricity of gasoline?

-Uwe-

 

[davisev5225]

Huh? How does ethanol help with the lubricity of gasoline?

-Uwe-

Info from a mechanic who's been working on cars longer than I've been alive. He's (almost) never wrong, so I trusted without verifying. Now that I've Googled it (which I should have done to start with...), I see he was wrong. I've updated my post accordingly.