Dock,
Very interesting!
The 996TT wasn't in existence at that time, other than in final development. I wonder if the rigorous usages and mod fever of the 996TT owners would change that directive.
So, by your post, it seems 5W50 is acceptable but 15W50 is not.
Care to comment? 1999Porsche911, care to comment as well?

 

Where did you find that info? The difference in the HTHS Viscosity, mPa·s @ 150ºC ASTM D 4683 between the 0w40 and 15w50 is HUGE. 3.6 versus 4.3. As per Mobil 1 themselves.

 

Ken - My bad. I didn't read the bulletin header close enough...it's dated 11-30-01 and states that it applies to all 2001 and newer 996 Turbos.

 

Yes.

Some years back Porsche told me that the 0W oil was for engine protection at start up.

Also, 0W/5W/15W all provide the same protection at +20F. The advantage of each lower numbered oil is it's ability to provide protection at lower temertures.

 

I have a Porsche technical service bulletin dated 7-9-04. For some reason castrol Syntec 5w50 is no longer included. It was included in a 2003 TSB. The TSB's are available on RennTech.org.
Included in the 7-04 approved oils are
Castrol syntec 5w40
Mobil 1 0w40
Mobil 1 5w40 and 5w50 (I believe these are Euro versions, not the Truck and SUV)
Kendall GT1 5w40
Motul 6100 and 8100 0w40 and 5w40
Pennzoil/Quaker state european formula 5w40
Valvoline synpower 5w40 and 0w40

I believe Mobil decided not to seek the European ACEA A3 approval for Truck and SUV only for marketing reasons. from what I've read it would easily pass ACEA A3.

 

If you want to get the HTHS up consider adding GM Engine Oil Suppliment. It has 6500 PPM ZDDP. Adding only 1 ounce to 8 quarts will increase the oil's ZDDP by 50 PPM.
Another Additive that looks good is Valvoline Synpower Oil Treatment iin the 15 oz. bottle. It has 3500 PPM MolyDTP and 2500 PPM Zinc. I'm adding 2 ounces of EOS and 8 ounces of Synpower at each oil change to add 175 PPM ZDDP and 100PPM moly.

 

Have you seen this

https://www.amsoil.com/storefront/afl.aspx

 

From what I've read, the highest engine wear occurs at start up. If this is true, then zero weight oil flows through the engine much more quickly than the five weight - reducing start up wear.

As for protection at operating temperature, how much HTHS viscosity is enough? Do we know what the Turbo's minimum required HTHS viscosity really is? I really doubt Porsche would require an oil that "just met" the minimum.

 

I would think Mobil One 10W-40 Exended Performance would be one oil to consider using in the summer months but I've never seen it on the shelf anywhere.

I don't see the point in going to a 50 weight oil. All it is costing is power. And in return for what?

Mobil One 0W-40 still seems an excellent choice to me.

Stephen

 

It seems that Mobil decided not to distribute the 10w40 Mobil 1 EP.

 

I haven't found it on the shelves. I wonder if it is even available from the distributors?

Stephen

 

I agree.

 

I'm curious as to why no one commented about the Amsoil. I'm told it out performs Mobil One. Not looking for a flaming just curious

 

Amsoil is good oil. Its sold and marketed direct like Amway products. If you're going to use a more expensive somewhat difficult to obtain oil like Amsoil you might as well get Redline instead.

 

I would like to add a small vote for the Motul brand here. It is approved by Porsche, and is available in higher end retail establishments. I use the 0-40 and so far the engine hasn't fallen out of the car....sorry but it's pretty hard to say that one oil has any demonstrably better characteristics until you have pulled down a few motors.

Not connection to Motul, just like the product.