What oil viscosity?

Hello everyone!

I'll be needing an oil change soon. I know that the VW 50500 specification is important. The question of oil viscosity comes up again.
Ja ich weiß: siehe Betriebsanleitung...
Here it is:

A stands for Otto, and B stands for Diesel.

To add to the confusion, here's a picture from my DIY book:

Here is A: multi-grade oil, and B: single-grade oil.

According to my DIY book, the only oil that should be used is 15W40. The book states that oils with a viscosity rating 'below' 15 will have their molecular chains sheared off over time, causing the oil to become too thin.

As is commonly known, the number following the "W" indicates how the viscosity behaves at high temperatures, while the number preceding the "W" corresponds to its behavior at low temperatures.
Therefore, according to my opinion, an XW40 lubricant should have the same viscosity at high temperatures regardless of the first number. However, this contradicts the diagrams.

Currently, I'm using a 15W40 oil that meets the VW standard. However, since winter is approaching, I want to switch to a 5W40. While I know that some people in the forum even use a 0W30 in this engine, I'm somewhat skeptical about that.

Okay, long text short question: Has the quality of oil improved so much in recent years that I can now use a 5W40 or even a 0W40?

(P.S.: I know myself that it's boring to always answer the same questions, but I can't find a satisfactory answer anywhere. )

Hi,
Is this a Beetle book or about the VW Golf I?
"The days of single-grade oil are over; you can't even find it in regular stores anymore. 15W40 is being heavily discounted, 10W40 is a simple standard, and 5W40 is generally good and, thanks to its synthetic base oil, doesn't break down as quickly."
0W30 is only suitable for engines designed for it, while 10W60 is for (wannabe) racing drivers.

Thank you for the answer!

christians wrote:

ist das ein Käferbuch oder vom GolfI?

A "Do-it-yourself" manual for my vehicle.
Well, you can't always believe everything you read in books.

I will just use a synthetic 5W40 and forget about my worries .

I bought some mineral oil for my Golf (model year 1996) from a dealer, it was new oil.

Since my first oil change, I've been using full synthetic 5W40 and haven't had any problems. Whether it helps the car start better in winter, I don't know, because it always starts immediately...

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

I don't have any problems with the engine starting, but you can definitely notice how much better a cold engine runs with higher-quality oil.

I just had the oil changed in my 1Z yesterday.
Since I purchased the vehicle, I have continuously used CASTROL GTD oil (which now includes the 'Magnatec' additive) with a viscosity of 10W-40.
Since I've been very happy with my Golf so far, I'll continue to use it (…never change a winning team!!!).

I now own my third Golf 1.6 TD, and since the introduction of Castrol GTD about 10 years ago, I have driven these vehicles for approximately 400,000 km exclusively with this oil – both in winter and summer, even though 10W-40 is technically not approved by VW for the higher temperatures during the summer months. Despite the high mileage of all three engines (>200,000 km) and a 'spirited' driving style, I have never experienced major engine damage and always had relatively low oil consumption.

Due to the frequent oil change intervals of the older engines (officially 7,500 km), more expensive types of oil are not worth it. Full synthetic oil would give me concerns with the older engines, as it can dissolve deposits and cause blockages.

@Golf2TD: The story about 'full synthetic oil would cause problems with older engines because it can dissolve deposits and cause blockages' is an old myth that persists. It's true that good oil can dissolve existing deposits and keep them suspended for a long time. However, it's not true that such oil immediately removes deposits 'in chunks.' (Even if: My AXR engine has an oil filter ).With a poor quality 15W-40 oil, deposits can build up in the grooves of the piston rings, leading to increased oil consumption. If you then use a good quality oil (even another 15W-40 with a solid base oil), these deposits will dissolve, the piston rings will seal again, and the engine will consume less oil. However, if you use a poor quality 5W-40 instead of a good 15W-40, the deposits will not dissolve, and oil consumption may slightly increase.Good oil is characterized by having a high-quality base oil to which only a few viscosity index improvers need to be added to achieve the desired viscosity, because: additives wear out faster than the base oil. Furthermore, it should be able to keep as many particles as possible suspended.

Regards,
Sure, here is the translation of the text from German to English:

'Micha'

Bei deinem DIY Buch benutzen die sicher noch die Druckplatten vom Käfer. Naja Scherz bei Seite. In anbetracht der zahlreichen Möglichkeiten seinem Motor Öl zu verabreichen muss man sich wirklich informieren. In meinen kommt das Longlife Öl und ich fahre das castrol SLX und bin sehr zufrieden. Es handelt sich um ein 0W-30 Öl. Es ist sicher nicht das Beste allerdings im Internet recht einfach und günstig zu erhalten. VUnfortunately, it's not available at good prices from local auto parts stores, as they often employ the tactic of doubling the oil change interval and then correspondingly increasing the price of the oil.
Otherwise, people's stomachs will rumble.

@Bee

Is that comparison between the 15W40 and the 5W40 something you're actually serious about?

Best regards, WarLord.

Hi 'Warlord',

Where did I directly compare a 15W-40 oil with a 5W-40 oil?
I wanted to emphasize that with oil, it's not just about the viscosity. The designation '5W-40' doesn't tell you anything about the quality of the oil. That's why I included those attributes before the viscosity in my previous post.
Can you agree with that?

I assume we can agree that, aside from the type of oil (such as mineral, HC, semi-synthetic, and fully synthetic), there are significant differences between a 5W-40 and a 15W-40 oil.


Regards,
Sure, here is the translation of the text from German to English:

'Micha'