More modern oil options for a Porsche 944?

[AK944]

I've got an '85 Porsche 944 as a project car that I've been running 20w50 Valvoline VR1 in without issues. But, getting bored while the car is in storage, I figured I'd ask people who know way more about oil than I do if there is a better option I could try. This is mostly for my own curiosity, and the fact that its kind of annoying that they only sell the VR1 in 1qt bottles up here in Canada so I have to end up buying 7 small bottles every oil change.

The consensus I've seen in the 944 community is these engines need a heavy oil with lots of zddp (~1300 ppm) with the latter requirement being driven by the flat tappet design of the lifters. Based on things I've read on here about other older vehicles, it seems like the requirements laid out in the owners manuals tended to be driven by the available technology when they were new, and I assume we've come a long way in 40 years.

I know 80s BMW owners sometimes run more modern oils with lighter weights than the 20w 50 a lot of them were specified to run, but the valvetrain designs on those engines, to my knowledge, differ significantly from those of the 944 and the other 80s water cooled Porsches. Porsche Classic now sells their own synthetic 10w50 for the 924, 928, 944, and 968 but I haven't seen much feedback on it, probably because it costs significantly more than the VR1 everyone uses.

I'm mostly just wondering if there is a readily available/relatively affordable alternative to the VR1 which is worth trying, either with more modern technology or just an alternative conventional oil (ie. LiquiMoly's 20w50 offerings or Castrol GTX Classic).

 

[GI_GRIFF]

https://www.liqui-moly.com/en/us/mos2-antifriction-sae-10w-40-p000207.html#2043

https://www.ecstuning.com/b-liqui_moly-parts/10w40-m0s2-anti-friction-motor-oil-5-liters/2043~liq/

https://www.fcpeuro.com/products/10w-40-motor-oil-semi-synthetic-5-liters-liqui-moly-lm2043

This is what I found. There are members on the site here that may show up that are MUCH smarter than I am on these European cars. Mobil and Castrol probably make oils that will work for you also. You may want to contact tech support of these different oil companies to get advice.

 

[Hohn]

I’m interested it what our seasoned members have to say, Many modern oils do not need nearly as much ZDDP to protect flat tappet engines because the calcium reductions in detergency make the lower ZDDP just as effective.

I’d think a Mobil 1 15w50 or even a Euro full SAPS 40 grade is probably quite sufficient. But I don’t know Porsches, so I’m speculating.

 

[BMWTurboDzl]

LiquiMoly has some 10w-50/40 MoS2 oils

 

[boom10ful]

I've been running 15W-40 Shell Rotella full synthetic in mine for a few years now with no issues.

 

[GI_GRIFF]

I’m interested it what our seasoned members have to say, Many modern oils do not need nearly as much ZDDP to protect flat tappet engines because the calcium reductions in detergency make the lower ZDDP just as effective. @Hohn on this, I want to read

I’m interested it what our seasoned members have to say, Many modern oils do not need nearly as much ZDDP to protect flat tappet engines because the calcium reductions in detergency make the lower ZDDP just as effective.

I’d think a Mobil 1 15w50 or even a Euro full SAPS 40 grade is probably quite sufficient. But I don’t know Porsches, so I’m speculating.

What @Hohn said!

 

[marc1]

Mobil 1 15w50 is readily available at Canadian Tire.

https://www.mobil.com/en/lubricants/for-personal-vehicles/our-products/products/mobil-1-15w-50

https://www.mobil.com/lubricants/-/...engine-oils-product-guide-sheet--may-2022.pdf

https://www.canadiantire.ca/en/pdp/mobil-1tm15w50-synthetic-engine-motor-oil-1-l-0289423p.html

The latest info from Mobil 1puts the P and Zn at 1200 and 1300 respectively in the 15w50.

 

[scrllock]

The owner's manual is interesting:

Both because of the multigrade ranges (5w20 only up to -10C ambient! Only use 10w40 if the air is under 90F!) and the "fuel efficient" oils having rather different ranges. Also love the note "before selecting these unconventional oils, consult your Porsche dealer."

Not sure if FCPeuro is viable in canada, but you can get the 15w50 and 20w50 classic with the lifetime replacement:

https://www.fcpeuro.com/products/classic-2100-15w-50-engine-oil-2-liters-motul-104512
https://www.fcpeuro.com/products/vw-engine-oil-motul-110621


Probably hard to beat the pricing on VR1 otherwise. And it's known to work for you, why change?

 

[altaylar]

I would certainly use Valvoline Restore and Protect 20W50 with no doubt. Very affordable, and exceptionally good oil for the classics

 

[Patman]

If you’re just driving this on the street with no track usage does it really need a 50 grade? Wouldn’t Mobil 1 0w-40 be just about perfect here? It even happens to be on sale at Canadian Tire right now, $37.99 for a jug

 

[kschachn]

How is it that you know a modern oil with A40 approval isn’t proper for your vehicle?

 

[altaylar]

How is it that you know a modern oil with A40 approval isn’t proper for your vehicle?

we flat tapped owners heard/read somewhere that the low zddp in modern oil destroys our engines. Many of us logically understand that it is not true, but emotionally we feel better if we feel our engines are better protected.

after spending so much time this forum, I think that peace of mind is what we are after, not necessarily the optimal oil choice. many of us buy boutique oil knowing even if we use Kirkland we will not see an oil related issue during our ownership

 

[kschachn]

we flat tapped owners heard/read somewhere that the low zddp in modern oil destroys our engine. Many of us logically understand that it is not true, but emotionally we feel better if we feel our engines are better protected.

after spending so much time this forum, I think that peace of mind is what we are after, not necessarily the optimal oil choice. many of us buy boutique oil knowing even if we use Kirkland we will not see an oil related issue during our ownership

Mhm. Somewhere you say?

Nowhere did I suggest Kirkland or an ILSAC oil. A40 is not that.

Do you know how much ZDDP is required for an already broken-in flat tappet engine? Do you know how much ZDDP Mobil 1 0W-40 has?

 

[AK944]

If you’re just driving this on the street with no track usage does it really need a 50 grade? Wouldn’t Mobil 1 0w-40 be just about perfect here? It even happens to be on sale at Canadian Tire right now, $37.99 for a jug

I know 944 engine builders/mechanics that I've talked to seem to suggest the viscosity on a modern Xw40 is likely too thin at operating temperature but I would be interested to see if there is a reason I can get away with that lower viscosity. The main concern I've seen about w numbers much lower than 20 seems to have been with cars that have the 16v head not building pressure to the hydraulic tensioner on the chain driving the exhaust cam.

How is it that you know a modern oil with A40 approval isn’t proper for your vehicle?

To be honest I'm not 100% sure that an A40 spec oil/0w40 wouldn't work, but I know that Porsche's website says to use their 10w50 as opposed to backdating the A40 spec like BMW did with applying the LL specs on their older cars. Of course, that could be to push the Porsche classic product.

 

[RBT]

The manual tells you what you need to know. If you want to change from a 20w50, go with a 15w40 or 15w50. Lower viscosity oils are unlikely to damage anything with mild street use but you may see (probably will see) greater consumption.

Also please don’t believe what you read about start up wear with 20w50. Anyone who has disassembled a motor can tell you that an oil film stays on the moving parts for a very long time and the parts will be well lubricated on start up and the motor will build oil pressure almost immediately if healthy.

Good luck with it. Those are nice cars.

 

[Mackelroy]

not a fan of castrol gtx classic , too much wax

 

[AK944]

Another point of data, on some older forum threads, I've seen people claiming to run the 10w60 synthetic that a lot of BMW M cars have specified without issue. I vaguely remember reading on here that it shears down to a 50 weight relatively quickly, but I wonder if more knowledgeable people than me can speak to it being an option.

I also think I'll make a list later today of the options discussed so far and what they cost to hopefully get some opinions!

 

[Nessism1]

Mobil 1 15W-50 or 0W-40 would both be a safe bet. The 15W-50 has a good bit more ZDDP, if you want to max out on that.

 

[kschachn]

I know 944 engine builders/mechanics that I've talked to seem to suggest the viscosity on a modern Xw40 is likely too thin at operating temperature but I would be interested to see if there is a reason I can get away with that lower viscosity. The main concern I've seen about w numbers much lower than 20 seems to have been with cars that have the 16v head not building pressure to the hydraulic tensioner on the chain driving the exhaust cam.

To be honest I'm not 100% sure that an A40 spec oil/0w40 wouldn't work, but I know that Porsche's website says to use their 10w50 as opposed to backdating the A40 spec like BMW did with applying the LL specs on their older cars. Of course, that could be to push the Porsche classic product.

The winter rating has little or nothing to do with engine protection. If you’re really worried about sufficient HT/HS then Mobil 1 5W-50 has Porsche A40 approval. You would have a difficult time doing better than that.

 

[altaylar]

Mhm. Somewhere you say?

Nowhere did I suggest Kirkland or an ILSAC oil. A40 is not that.

Do you know how much ZDDP is required for an already broken-in flat tappet engine? Do you know how much ZDDP Mobil 1 0W-40 has?

Nope, us mortals don't know any of those unfortunately