Motor Oil Recommendations

[Chris Pomares]

I was a Mobil Automotive rep in Colorado some time back. I was always a Mobil 1 guy. I still think it's very good. I have since changed 2 times on my Porsche. I went from Mobil 1 20-50 Air Cooled motorcycle oil, to Gibbs, now called Driven, to Champion. I buy my oil from a top domestic engine builder in the Denver area. This guy does extensive dyno runs with varying oils. He has since changed from Driven to Champion. With his testing he has found Champion to protect the cams and bearings the best of all the oils he's used. My car holds 14 quarts, so a oil change runs about $200.00. But that's cheap insurance considering a new POLO engine today runs $75 to $100K.

https://www.championbrands.com/

[prs356]

My mechanic recommends Red Line 20W-50 for my 65 911.

[sanders]

Where I have 550,000 miles on my Suburban using Mobile1, I use VR1 in both racing and road use early 911s. I called WebCam 20 years ago and complained about lobe wear on their regrinds on my race car. The first thing they said was, "you're using Mobile1 aren't you?" "You need to use a quality conventional oil, like Valvoline". Since then, nothing but VR1 and no problems.

[RSTarga]

Where I have 550,000 miles on my Suburban using Mobile1, I use VR1 in both racing and road use early 911s. I called WebCam 20 years ago and complained about lobe wear on their regrinds on my race car. The first thing they said was, "you're using Mobile1 aren't you?" "You need to use a quality conventional oil, like Valvoline". Since then, nothing but VR1 and no problems.

Never had cam wear on my cars from M1, isn't 20w50 VR1 a synthetic also? Changing oil often is the best insurance.
VR1 is excellent too.

[richemj]

Anyone have informed knowledge or thoughts on the newer Porsche Classic 20W50 for up to 3.0L engines, and 10W60 for over 3.0L? I've been a BradPenn fan for 20yrs... but thinking of going the new route. Thoughts?

[911MRP]

As historical context the original lubricant requirement as shown in the Porsche tech specs booklet of 72/3
It had to be the older HD — Heavy Duty or API MS-Most Severe or classification SD

Heavy Duty for 911 not just regular or even premium motor oil of the day.

Oil technology has moved on significantly in fifty years since they affixed a Shell sticker to the MFI air-box but in 1973 these were some comments in the magazine road tests of the then brand new Porsche 911 Carrera RS



The testers were surprised it was straight mineral oil. Even by 1975 the new 911 Turbo was using the same straight mineral oil rather than the Multigrade that were being used —I have that turbo article somewhere.

Also have this empty (also for display) imperial one gallon can of shell rotella like the importer slung in the RS to be sure the road test journalists didn’t run out of engine lubricant when thrashing the press demo RHD 73 RS.


Around 1970, the API with SAE established a classification system in part related to warrant considerations with two main categories, "S" for spark-ignition (ie petrol) engines, and “C” for compression-ignition (ie diesel) engines. There were related test procedures and performance metrics.

Around the time the 72 911 with 2.4 litre motor were being developed oils could be covered by just four S classifications SA through SD and — (plus less relevant four “C”). This system got more classifications over the years, as summarised in this graphic:


My display Rotella gallon can shows “HD” as well as API “SE - this came in around after the 72/3 911 motors developed so maybe it’s why SD not SE is shown in the Porsche tech spec of 72/3. With SE oil classification being related to 1972 warranty would soon hit the market so likely around time 73 model needed a oil change




This is the wording from a September 1975 advert for Shell Rotella TX Oils around time turbo came to market pitching it for high performance petrol engine applications, not as often thought only commercial diesels:
“These are the oils for the hardworked mixed fleet. Shell Rotella TX Oils are premium lubricants designed for the higher powered naturally aspirated and turbocharged diesel engines. They also fully satisfy the requirements of high performance petrol engines.
* Exceptional engine protection, even at sustained high speeds and loads.
High temperature diesel and petrol engine lubrication performance to MIL-L-2104C * Series 3 and MILL-46152 specifications.
* Outstanding low temperature sludge control for short-haul working.
* Dispersancy and oxidation stability excellent in large and small diesels, and in petrol engines too. Stay-in-grade 20W '40 multiviscosity version for low and controlled oil consumption, lower fuel consumption, and fewer oil changes.
* Also available in single grades. So, even if you combine petroldriven vans on local deliveries with high power diesels on long distance trucking, you can enjoy one-oil fleet lubrication. Once you've tried our 20W/40 shear-stable multigrade, you'll never turn back.”

This an old Shell Rotella drum I have (for decoration) that matches the winter grade in shown Porsche tech specs book:

This is photo of what seems to be a similar an old Shell oil drum under a bench somewhere in the in Porsche factory back in the day


Wandering down memory lane is straying from the latest recommended lubricant product formulations (to be clear by doing so not making a current recommendation since the SD spec oil recommended in the 72/3 Porsche tech spec booklet are now regarded as obsolete and maybe even harmful to equipment apparently ? )

So if stuck maybe not wise to befriend an old farmer or an old trucker even if they might still have something similar kicking around to what 911 had as the factory fill like this Carrera RS at new back in the spring or summer of 73 (est date of photo based on having a single bolt fan strap)



It’s many years since I worked in oil and gas industry so open to be corrected by and learn from the experts

Enough historical stuff back to the question of what people are using today
Steve

[72targa]

^^^^ wonderful history capture!

[Chuck Miller]

Very well done Steve...

[FlyingFinn911]

I use Shell Rotella T4 15w-40 in my 2.0L. Conventional oil, high zinc content

[bigcity911s]

If you want to go down that hole further...

https://forums.pelicanparts.com/911-...test-zddp.html