juankimalo

I wonder why Porsche recomends Mobil 1 0W40.
The core of a 911 is a high performance engine. I know it's perfectly covered by this fantastic oil. Mobil 1 0W40 is enough to prevent wear , and it's good enough to protect the engine on extreme weather conditions too .
But i was thinking about Castrol RS 10W60, another wonderful product with different viscosity. Perhaps this is the ideal viscosity to be mounted in warm and hot climate regions.
I live in Spain. In summer we have 2 or 3 months very hot. Temperatures raise 40º C or a bit more
¿what do you think about this?

jb26jb

I believe Mobil 1 has a 5-50 available in Europe but not here in the States that would probably be great for the summer months.

marlinspike

I think 10w is needlessly thick when cold, you might not get proper lubrication. You get more hp with thinner oils so why bother if 0-40 is protecting (and a synthetic 0-40 will protect).
RIchard

1999Porsche911

Contrary to the marketing of Mobil, the 0W40 DOES NOT provide for proper lubrication in hotter climates at startup. Open your window and just listen to the tick, tick tick, when you park your car after a good run and let it sit over night. That's the sound of your lifters being void of enough oil after the Mobil water drained out overnight.

Now, change the oil to a 5W50 or 15W50 and listen again.

The viscosity of 40 on the hot side is laughable when your oil temps are running at 230F, 240F, 250F..... But, if you don't plan on keeping the car long, it doesn't matter.

Gus B.

So would Castrol 10W60 or Mobil 1 15-50 be a better choice for these engines when weather never falls below 85F? Just changed the oil in mine and I put Mobil 1 15-50 as the 0-40 was not available. The Mobil oil is $7.50 per quart here vs. $32 per liter for the Castrol.

1999Porsche911

I run the Castrol 5W50 or Mobil 15W50 in summer.

juankimalo

There is a thing that i'm sure yet:
When summer comes, the engine needs more lubrication in extreme conditions, and as you say, it would be better to change oil to a 5W50
Thanks

marlinspike

Castrol RS is a racing oil, don't waste your money. Racing oils mean you are paying many many times more to get another 1 or 2 horsepower. Also, while I'm not sure if this applies to RS since RS is API approved, typically racing oils have higher amounts of zinc and sulfur and need to be changed more often (like every 5 hours of running). If you really want to go all out get some Joe Gibbs racing oil...sure you'll have to blueprint your engine first (infact, invent a new process of re-blueprinting by which I mean don't only blueprint it but also close up all the gaps) and change your oil every 500 miles.

Tbred911

seems like castrol 5W50 can be used even in the winter no? after all it does have the 5W rating...?

1999Porsche911

I either use 5W40 or 5W50 in the winter. Either one is fine, it just depends what you can find at the time. The 5W50 keeps the pressure off you when running it hard on warmer winter or early spring days.

JasonAndreas

They also recommend Castrol RS "Road and Track" and Castrol RS "Power and Protection" in 5w-40 and 0w-40 weights.

ebaker

Castrol Syntec 5w50 was removed from the Porsche approved oils list. Not sure why.

djantlive

Can anyone confirm the tapping sound is due to oil starvation at the lifters? I though oil only get injected to the valves/lifters to cool a hot running engine.

I heard the tapping sound when car sits for 2+ weeks. This happened on my 98 E320 a few times. If a heavier old should be used, I'd definitely try it next time.

Riad

I always assumed that sound was the cat converters... sure about this??

Chuck Jones

As I understand it...pretty much regardless of what oil you use, if you let your car sit long enough, the oil will drain down by the simple rule of gravity. The tapping sound you hear at start up is the valves making noise before the oil can get pumped up to them. That's why they recommend you give the car a bit of time to slightly warm up so that the oil can get pumped to the engine parts before you stomp on it and unnecessarily run an oil depleted part of the engine. Some of the guys advocate just getting in there and taking off cold, while others suggest a little more restraint and not to run over 2500 rpm until the oil gets properly circulated by the engine warming up a bit. Moderation seems prudent to me. The real issue in the summertime would be to use an oil that had enough viscosity so that it didn't run like water through the engine and out the rings/valves. At least that's how I understand it...and there are folks on this board a lot more knowledgeable than myself.