Oil Preference

DougE

DougE

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I have a 1972 3.0cs, I rebuilt the engine many years ago, but I've only clocked 20,000 miles since. I broke the engine in on Castrol GTX 20-50, on the first oil change, I switched to
Redline 20-50.

Redline has become very expensive and somewhat difficult to find. I am familiar with Valvoline VR1 racing oil. Valvoline has introduced VR1 20-50 full synthetic. The reviews and tests I've read about VR1 synthetic are very positive, so I just did an oil change and switched to VR1 synthetic. It's blue like ATE racing brake fluid.

What is the favorite oil for your coupes?
Thanks, Douglas
 
I use Mob 1 15W-50 in my CS. I used that oil in the M10 in my 2002 for nearly 30 years also (before the Coupe). Has always worked great for me.
See graphic below showing the page of the owners manual that discusses the different weights to use. There was a short time in the very early 1980's when I used Castrol 20W-50. I noticed a very definitive change when I switched to the synthetic. Been using Mob 1 products on all my cars since.
Almost 2 million miles all told between the cars I have had.

p_061.jpg
 
A buddy of mine who lives nearby is a retire BMW mechanic and has run Mobil 1 in all his cars and recommended it to all his clients for decades. He has never had a problem in any of either his cars or his client's cars running Mobil 1.

That said, I begain using Redline 20w50 when I bought my car (before I met my car mechanic friend) and have not changed.
 
Anyone had any experience with this:

Castrol GTX Classic 20W-50 Conventional Motor Oil​

I just order two cases so I hope good, if not, only pouring one quart in until my oil pan gasket is changed and oil/filter, etc. Didn't BMW originally recommend Castrol GTX? High zinc contect in this "new-er" mix. I like it because not synthetic or a hybrid.

EDIT: I use to use Brad Penn in the Porsche but saw they got bought out and mix changed a bit but also I think better for air (oil) cooled motors but open to comments on both.
 
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Nachtycoupe said:
Anyone had any experience with this:

Castrol GTX Classic 20W-50 Conventional Motor Oil​

I just order two cases so I hope good, if not, only pouring one quart in until my oil pan gasket is changed and oil/filter, etc. Didn't BMW originally recommend Castrol GTX? High zinc contect in this "new-er" mix. I like it because not synthetic or a hybrid.

EDIT: I use to use Brad Penn in the Porsche but saw they got bought out and mix changed a bit but also I think better for air (oil) cooled motors but open to comments on both.
Click to expand...


yes I used it regularly until i found and was advised to use castrol magnatec 10w40 as a more modern oil
but GTX is a good oli for our engines
 
i have been told that essentially any modern oil is going to be much better than old oils
also that classic castrol oils are not better ones when compared to normal oil (so no worth payong more for them)
the iconic oils mobil1, redline,... and so on are perfect but again...

p.s. oil threads are recurrent and very disputed, i recall @Arde comment about oils, race and religion to be three of the most controversial topics
 
My original mechanic was a Redline person but I forget if it was for engine oil or transmission...
I think he was actually doing a synthetic blend 50-50. @deQuincey may be able to promote the 50-50 blend idea for the other two controversial topics and settle them...
 
Arde said:
My original mechanic was a Redline person but I forget if it was for engine oil or transmission...
I think he was actually doing a synthetic blend 50-50. @deQuincey may be able to promote the 50-50 blend idea for the other two controversial topics and settle them...
Click to expand...
Probably transmission - the 50/50 combo is Redline MTL and 90w gear oil promoted by Carl Nelson which many of us use.
 
Arde said:
My original mechanic was a Redline person but I forget if it was for engine oil or transmission...
I think he was actually doing a synthetic blend 50-50. @deQuincey may be able to promote the 50-50 blend idea for the other two controversial topics and settle them...
Click to expand...

50/50 is always a wrong recipe, me thinks, but it is highly well seen as a democratic thing
i vote for one oil change using one brand and the next one using other, or one weekend go to beach next one to the mountain, or blue socks tomorrow, next one brown; other examples may not be appropriate for minors so i will refrain from disclosing them.
 
Uh-oh... 50/50 is not good? But -
Castrol Magnatec 10W-40 is a part-synthetic engine oil designed for various gasoline engines. The other "part" is conventional. But they keep their ratio a secret (50/50 ?). Always a fun thread to read on! :)

I had a conversation with AI on this topic - more specifically synthetic and semi- used in vintage motors. Occasionally AI is not fully trained in some topics but I think answers below seem right to me. Read on if your interested. I guess we found those commenting for synthetics and semi- have made some good choices. I'm not advocating as I still use conventional. Okay, pasting below - do we learn anything that Naughtycoupe, Nosmonket, Bert and Lip277 didn't know?

ChatGPT said:
Yes, vintage motors (engines designed before the advent of synthetic oils) can often use synthetic oil, but there are some important caveats and considerations:
Pros of Using Synthetic Oil in Vintage Engines:
  1. Superior Lubrication: Synthetic oils offer better film strength and flow characteristics, especially in extreme temperatures.
  2. Reduced Sludge and Deposits: They resist oxidation and thermal breakdown better than conventional oils.
  3. Improved Engine Protection: Especially beneficial for engines that may sit unused for long periods.
Potential Issues:
  1. Seal Compatibility: Older engines often used natural rubber seals that synthetic oils may degrade or shrink, potentially causing leaks.
  2. Cleaning Effect: Synthetic oils have high detergent properties, which can dislodge old sludge and cause clogging in oil passages if not managed carefully.
  3. Additive Packages: Some synthetic oils lack high levels of zinc/phosphorus (ZDDP), which is critical for flat-tappet cam engines common in pre-1980s vehicles.
Recommendations:
  • Check for Seal Compatibility: Use synthetic oils labeled as "compatible with older engines" or consider high-mileage synthetic blends.
  • Look for High ZDDP Levels: Use a synthetic oil formulated for classic cars (e.g., with ZDDP additives) if your engine has flat-tappet cams.
  • Start with Caution: If switching, change oil and filter more frequently at first to catch any loosened deposits as synthetics have higher detergent levels.
  • Synthetic Blends: A compromise option offering better performance than conventional oil while reducing risk of leaks or seal issues.
Would you like a list of specific synthetic oils formulated for classic or vintage engines?
You said:
Yes

ChatGPT said:
Yes, vintage and classic engines can benefit from synthetic oils, provided the oil is formulated with high levels of zinc dialkyldithiophosphate (ZDDP) to protect flat-tappet camshafts and other critical engine components. Here are some top synthetic oils designed specifically for vintage and classic engines.
Top Picks Explained:
  • Valvoline VR1 20W-50 Racing Motor Oil: This oil is formulated with high levels of ZDDP, making it ideal for flat-tappet camshafts.
  • Royal Purple HPS High Performance Street Motor Oil: Offers enhanced wear protection and improved performance for classic engines.
  • PennGrade 1 20W-50 Racing Oil: An affordable option that doesn't compromise on quality, suitable for vintage engines.
When selecting an oil, consider the specific requirements of your engine, including the need for ZDDP additives, viscosity, and compatibility with vintage components. Always consult your engine's manufacturer recommendations and, if in doubt, consult with a professional mechanic familiar with classic vehicles.

You said:
does Mobile 1 have high ZDDP additives?

ChatGPT said:
Yes, Mobil 1 offers motor oils with varying levels of zinc dialkyldithiophosphate (ZDDP), an essential anti-wear additive for older engines, particularly those with flat-tappet camshafts. However, the ZDDP content varies across different Mobil 1 formulations.

Mobil 1 Oils with Higher ZDDP Levels
Mobil 1 has specific oils formulated with higher ZDDP concentrations to provide enhanced protection for older engines:
  • Mobil 1™ FS 0W-40: Contains approximately 1,000 ppm of phosphorus, which translates to around 1,200 ppm of zinc. This formulation is suitable for many classic and high-performance engines.
  • Mobil 1™ High Mileage 10W-40: Also contains about 1,000 ppm of phosphorus, offering similar zinc levels to the 0W-40 variant. It's designed for vehicles with over 75,000 miles.
  • Mobil 1™ 15W-50: This oil has higher ZDDP levels, with phosphorus content around 1,200 ppm, equating to approximately 1,500 ppm of zinc. It's particularly beneficial for older engines requiring additional wear protection.
For vintage or performance engines, especially those with flat-tappet camshafts, it's crucial to select oils with adequate ZDDP levels to prevent premature wear. Mobil 1 oils like the 15W-50 variant offer higher ZDDP concentrations suitable for these applications.
However, it's important to note that while Mobil 1 oils with higher ZDDP levels are beneficial for older engines, they may not be suitable for modern vehicles equipped with catalytic converters and advanced emission systems. The elevated phosphorus content can potentially harm these components.

You said:
Do Castrol synthetic oils have high ZDDP levels?

ChatGPT said:
Castrol offers a range of synthetic and semi-synthetic motor oils, but their ZDDP (zinc dialkyldithiophosphate) content varies across different product lines. While modern formulations often have reduced ZDDP levels to meet current API standards, Castrol has developed specific oils designed for vintage and high-performance engines that contain higher ZDDP concentrations.

Castrol Oils with Higher ZDDP Levels
1. Castrol GTX Classic 20W-50
  • Formulation: High-zinc and phosphorus content
  • Designed for: Flat-tappet camshaft engines, classic cars, muscle cars, and racing applications
  • Key Features:
    • Provides extreme wear protection
    • Maintains a tough and thick oil film under severe conditions
    • Compatible with gasoline and alcohol-based fuels
  • Note: Not recommended for modern engines with catalytic converters or wet clutch applications
  • Availability: Available in 20W-50 grade
2. Castrol GTX High Mileage (Synthetic Blend)
  • Formulation: Synthetic blend with higher ZDDP levels than standard oils
  • Designed for: Vehicles with over 75,000 miles
  • Key Features:
    • Helps prevent oil burn-off and leaks
    • Provides enhanced wear protection
  • Note: While it contains more ZDDP than standard oils, it's not as high as the GTX Classic
  • Availability: Available in various grades, including 10W-30 and 20W-50
3. Castrol EDGE 10W-60
  • Formulation: Full synthetic with high ZDDP content
  • Designed for: High-performance and racing engines
  • Key Features:
    • Provides maximum strength under extreme pressure
    • Reduces metal-to-metal contact
  • Note: Suitable for engines requiring higher ZDDP levels
  • Availability: Available in 10W-60 grade
 
That seems like a good overall analysis, even for AI. The reason I stick to a traditional oil vs. Synthetic or Hybrid is because sometimes the synthetic can overly clean an older motor used to running on a conventional oil. With the added zinc and phosphorus, I figured about as true to what these M30 motors where used to.

Now, if I had a completely rebuilt, say, Metric Mechanic motor, brand spanking new everything, maybe then would I consider going synthetic or hybrid but I would obviously go by whatever Metric Mechanic says would be best. Unfortunately, I have a rebuilt newer head but tired bottom end and I'm afraid I might loosen too much "gunk" if I all of sudden switched to full synthetic. Hence, I'm replacing the oil pan seal soon because I can't stand any leaks whatsoever and replacing it all with the Castrol GTX Classic 20-50. It's not leaking much, but I hate even a drop. That is just my thinking, not an expert by any means.

I will be upset if the oil pan area still leaks after however. I will report back if that is the case.
 
Stevehose said:
no, just many years of e9 experience since the 80's.
Click to expand...

mixing oils is a serious thing
i hope he made some kind of analysis

I remember that phosphorus was incompatible with sodium, and in the field of anti-knock additives, there were products with sodium and others with phosphorus, and in both cases, the product manufacturers hid the composition, this was only found by means of a chemical analysis,



coupesport said:
Uh-oh... 50/50 is not good? But -
Castrol Magnatec 10W-40 is a part-synthetic engine oil designed for various gasoline engines. The other "part" is conventional. But they keep their ratio a secret (50/50 ?). Always a fun thread to read on! :)

I had a conversation with AI on this topic - more specifically synthetic and semi- used in vintage motors. Occasionally AI is not fully trained in some topics but I think answers below seem right to me. Read on if your interested. I guess we found those commenting for synthetics and semi- have made some good choices. I'm not advocating as I still use conventional. Okay, pasting below - do we learn anything that Naughtycoupe, Nosmonket, Bert and Lip277 didn't know?

ChatGPT said:
Yes, vintage motors (engines designed before the advent of synthetic oils) can often use synthetic oil, but there are some important caveats and considerations:
Pros of Using Synthetic Oil in Vintage Engines:
  1. Superior Lubrication: Synthetic oils offer better film strength and flow characteristics, especially in extreme temperatures.
  2. Reduced Sludge and Deposits: They resist oxidation and thermal breakdown better than conventional oils.
  3. Improved Engine Protection: Especially beneficial for engines that may sit unused for long periods.
Potential Issues:
  1. Seal Compatibility: Older engines often used natural rubber seals that synthetic oils may degrade or shrink, potentially causing leaks.
  2. Cleaning Effect: Synthetic oils have high detergent properties, which can dislodge old sludge and cause clogging in oil passages if not managed carefully.
  3. Additive Packages: Some synthetic oils lack high levels of zinc/phosphorus (ZDDP), which is critical for flat-tappet cam engines common in pre-1980s vehicles.
Recommendations:
  • Check for Seal Compatibility: Use synthetic oils labeled as "compatible with older engines" or consider high-mileage synthetic blends.
  • Look for High ZDDP Levels: Use a synthetic oil formulated for classic cars (e.g., with ZDDP additives) if your engine has flat-tappet cams.
  • Start with Caution: If switching, change oil and filter more frequently at first to catch any loosened deposits as synthetics have higher detergent levels.
  • Synthetic Blends: A compromise option offering better performance than conventional oil while reducing risk of leaks or seal issues.
Would you like a list of specific synthetic oils formulated for classic or vintage engines?
You said:
Yes

ChatGPT said:
Yes, vintage and classic engines can benefit from synthetic oils, provided the oil is formulated with high levels of zinc dialkyldithiophosphate (ZDDP) to protect flat-tappet camshafts and other critical engine components. Here are some top synthetic oils designed specifically for vintage and classic engines.
Top Picks Explained:
  • Valvoline VR1 20W-50 Racing Motor Oil: This oil is formulated with high levels of ZDDP, making it ideal for flat-tappet camshafts.
  • Royal Purple HPS High Performance Street Motor Oil: Offers enhanced wear protection and improved performance for classic engines.
  • PennGrade 1 20W-50 Racing Oil: An affordable option that doesn't compromise on quality, suitable for vintage engines.
When selecting an oil, consider the specific requirements of your engine, including the need for ZDDP additives, viscosity, and compatibility with vintage components. Always consult your engine's manufacturer recommendations and, if in doubt, consult with a professional mechanic familiar with classic vehicles.

You said:
does Mobile 1 have high ZDDP additives?

ChatGPT said:
Yes, Mobil 1 offers motor oils with varying levels of zinc dialkyldithiophosphate (ZDDP), an essential anti-wear additive for older engines, particularly those with flat-tappet camshafts. However, the ZDDP content varies across different Mobil 1 formulations.

Mobil 1 Oils with Higher ZDDP Levels
Mobil 1 has specific oils formulated with higher ZDDP concentrations to provide enhanced protection for older engines:
  • Mobil 1™ FS 0W-40: Contains approximately 1,000 ppm of phosphorus, which translates to around 1,200 ppm of zinc. This formulation is suitable for many classic and high-performance engines.
  • Mobil 1™ High Mileage 10W-40: Also contains about 1,000 ppm of phosphorus, offering similar zinc levels to the 0W-40 variant. It's designed for vehicles with over 75,000 miles.
  • Mobil 1™ 15W-50: This oil has higher ZDDP levels, with phosphorus content around 1,200 ppm, equating to approximately 1,500 ppm of zinc. It's particularly beneficial for older engines requiring additional wear protection.
For vintage or performance engines, especially those with flat-tappet camshafts, it's crucial to select oils with adequate ZDDP levels to prevent premature wear. Mobil 1 oils like the 15W-50 variant offer higher ZDDP concentrations suitable for these applications.
However, it's important to note that while Mobil 1 oils with higher ZDDP levels are beneficial for older engines, they may not be suitable for modern vehicles equipped with catalytic converters and advanced emission systems. The elevated phosphorus content can potentially harm these components.

You said:
Do Castrol synthetic oils have high ZDDP levels?

ChatGPT said:
Castrol offers a range of synthetic and semi-synthetic motor oils, but their ZDDP (zinc dialkyldithiophosphate) content varies across different product lines. While modern formulations often have reduced ZDDP levels to meet current API standards, Castrol has developed specific oils designed for vintage and high-performance engines that contain higher ZDDP concentrations.

Castrol Oils with Higher ZDDP Levels
1. Castrol GTX Classic 20W-50
  • Formulation: High-zinc and phosphorus content
  • Designed for: Flat-tappet camshaft engines, classic cars, muscle cars, and racing applications
  • Key Features:
    • Provides extreme wear protection
    • Maintains a tough and thick oil film under severe conditions
    • Compatible with gasoline and alcohol-based fuels
  • Note: Not recommended for modern engines with catalytic converters or wet clutch applications
  • Availability: Available in 20W-50 grade
2. Castrol GTX High Mileage (Synthetic Blend)
  • Formulation: Synthetic blend with higher ZDDP levels than standard oils
  • Designed for: Vehicles with over 75,000 miles
  • Key Features:
    • Helps prevent oil burn-off and leaks
    • Provides enhanced wear protection
  • Note: While it contains more ZDDP than standard oils, it's not as high as the GTX Classic
  • Availability: Available in various grades, including 10W-30 and 20W-50
3. Castrol EDGE 10W-60
  • Formulation: Full synthetic with high ZDDP content
  • Designed for: High-performance and racing engines
  • Key Features:
    • Provides maximum strength under extreme pressure
    • Reduces metal-to-metal contact
  • Note: Suitable for engines requiring higher ZDDP levels
  • Availability: Available in 10W-60 grade
Click to expand...

Yes I can be a bit incoherent
 
I just changed oil with: From Wallmart $28 for 5 quart

Mobil 1 Advanced Full Synthetic Motor Oil 15W-50​

 
deQuincey said:
mixing oils is a serious thing
i hope he made some kind of analysis

I remember that phosphorus was incompatible with sodium, and in the field of anti-knock additives, there were products with sodium and others with phosphorus, and in both cases, the product manufacturers hid the composition, this was only found by means of a chemical analysis,





Yes I can be a bit incoherent
Click to expand...
The 50/50 is for the transmission not the engine
 
Wobdog said:
I just changed oil with: From Wallmart $28 for 5 quart

Mobil 1 Advanced Full Synthetic Motor Oil 15W-50​

Click to expand...
Did you notice any leak after driving it say...10K miles? Just curious. Or any other issues? Or did you literally just change to full synthetic? Not many miles since? And shouldn't it take 6 quarts if replacing the filter at the same time?
 
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