apo128

Hi,

Doing an oil change next week and wanted some feedback.

This was my dad's car b/f he gave it to me and would have them use Castrol 5W40 Edge Synthetic(at least this is what they call it now) when they did the change - always brought his own oil. He seemed not to be very partial toward the Mobil that the dealer uses.

Any thoughts on the Castrol? It is just as good or better than the Mobil?

Thanks for the feedback.

Andrew

ca993twin

I'm not as concerned about the "brand" of oil as I am with the viscosity. 5W40 is NOT correct for any air-cooled Porsche. Use 15-50 or 20-50. I have been using the Mobil 1 V-Twin 20-50 to get more of the additives to protect our cams and flat-tappet lifters. I will mix this with the Mobil 1 15-50 around 50-50.

There are MANY oil-related threads on this forum. And there are many opinions on brands. But virtually everyone would agree with my comments about viscosity.

Texas993

Congrats Andrew.

I don't see much mention of Castrol on the many, many oil related posts. My current oil is the Mobil 1 Vtwin 20-50. Many use the Mobil 1 15-50 which is readily available at Walmart and less expensive.

Others use boutique brands like Brad Penn and Motul. I suggest that you do a search and decide for your self.

If you were to skip the search and are looking for a simple answer: most here would recommend the Mobil 1 V-twin.

Basal Skull

There was Castrol syntec 20w50 that's probably a good wt to use. I think the newer formulations (castrol edge are 0 or 5W - for newer cars). Everyone tends to use higher wt oil in our cars as above. Castrol in general have higher Zinc that our engines are supposed to like and the Castrol base synthetic oil that's used in all their oils are afaik a good hydro-cracked synthetic. I've tested it on cross bearing friction machines previously fwtw and are similar to Mobil 1.

ronnie993tt

+1 for the 50/50 M1 mix.

BLT4SPD

Castrol does make some good oils, but like with all brands, they make a wide range of oils to appeal to a wide range of consumers. As already mentioned, the MB1 V-Twin is going to be the favorite of most here and for good reason....it's a great oil, made with a great base stock with a great additive pack. Add to that, that you can walk into just about any local auto parts store and buy it off the shelf for $10/qt (in the motorcycle oil section) and it's hard not to like......I run it in my turbo for all the reasons mentioned.

However, if one is married to the Castrol brand and you want to get a VERY comparable oil to the MB1 V-Twin, you should also look to the Motorcycle oils and obtain the Power RS series (available in 20/50 and 10/40). Really a great oil and will be very, VERY superior to ANY of the off-the-shelf Castrol stuff that you are used to seeing at (insert you favorite oil retailer here). It can be had for $8.02/qt from Amazon with free shipping:

ca993twin

I just noticed in my latest issue of Hemmings Sports News (or some such title... I've already passed it along), Hemmings is advertising "Hemmings" oils in 3 viscosity ranges specifically formulated with the the additives for flat tappet engines. One of those is a 15W50. They sell a six pack for $69.95.

http://blog.hemmings.com/index.php/2...-classic-cars/

Interesting. I wonder how this would hold up for our high temp applications? What affect on our catalysts? Hmmm... food for thought.

993Godspeed

I use Mobil 1 0-40 it's what the dealer recommended to me? Should I be switching? Why? Thx

ca993twin

The dealer sees 95% water-cooled Porsches in their shops. They would prefer to use a single oil for all their service. Your engine requires a higher viscosity oil, and also needs higher levels of ZDDP and phosphorous for your flat tappets. Why does your dealer care if you wear your camshafts out prematurely? Its just more business for their shop.

993Godspeed

Thanks for the response. I will be switching!!

BLT4SPD

With that said, for something that you can stroll into WallyWorld and buy off the shelf, it’s a pretty good oil. 1000ppm on Phosphorous and 1100ppm on Zn. It’s one of the VERY few MB1 oils that you’ll find (in this country) that meets VW’s 505 spec, BMW’s LL01 spec and yes, Porsche’s A40. I have heard that it is made with different base stocks that the other MB1 products that we get here, which is why is carries the “European Formula” on its label. It’s my winter oil of choice in my turbo I5 Audi motor and it has served me well.

…..and with THAT said, I would agree that it’s not the best choice for the aircooled applications and I don’t/won’t run it in my 993 or 356.

apo128

Thanks to everyone for your feedback. It has been very helpful.

ca993twin

I wish you would state exactly which Mobil One oil you are talking about. Thanks.\

cgfen

Possibly true, but I'm a fan of using a lower viscosity rating oil for cold start conditions.
No way I'd run 15 - 50 in a car driven where starting ambient temps < 45 degrees or so.

Mobile 1 turbo Diesel 5 - 40 works for me and the latest Blackstone report says

"CRAIG: We like the looks of this Porsche at 31,000 miles. Universal averages are based on ~3,200 miles on the oil. That's close to the 3,800 miles on your oil and wear metals match up very well with averages.
That's a good indication that the mechanical parts in this engine are behaving as they should. No fuel dilution was present and the viscosity was normal for 5W/40. Low insolubles and silicon show good oil and air filtration. Nice engine and report.

Caveat, I top off oil with 15 - 50 over the course of a year (2 quarts?).
Final viscosity is probably closer to 9.5 - 47.

Cheers

Craig

BLT4SPD

Yeah, sorry about that. It probably sounded better in my head than it did on paper.

Summary: The 0/40 Mobil 1 that you can buy most everywhere is a VERY good oil considering its high availability and price point. It’s my winter oil of choice in my liquid cooled high-ish HP Audi I5 turbo motor.

However, I would agree with you that it is NOT the best choice for the air cooled motors and especially the turbo air cooled motors. _I_ do not run it in my 993 or my 356. Like most here, I opt for the V-Twin flavor of Mobil 1.