No, you are right, its not on their aaproved list, but I still use it and suggest it.....

My local Advance Auto Parts store advertised this special on Castrol Syntec: 5 qts plus filter, $27.99. I bought 10 qts of 10W40 for My Cayman S. They didn't have the proper filter so I substituted two filters for one of my other cars. Seems like a reasonable deal.

is Castrol Syntec 5w-50.

Last oil change for the Boxster and the Turbo I switched to Mobil 1 5w40 and will come the next oil change (summer) switch to Mobil 1 5w-50. Both of these are approved oils. A very nearby Mobil oil distributor tells me that the 5w-50 is a bit cheaper than the 5w-40 oil, too.

Sincerely,

MarcW.

This is a simple matter of specs and tests. I have the same use for porsche approved oils that i have for N spec cupholders.

It flows well at all but the craziest temperatures.

It has far better HTHS shear and durability over cycles than most 5w40 oils

It flies through ACEA testing while many need 10-20 repeat to get the coveted A3 rating (hmm, how do i know that?)

Is it ideal? No. I really want 10w40 edge with the european package. But i cant have it.

The basic porsche requirement is: a) meets A3; b) is 5w40 or close, for fuel economy cycle reasons

If you drive hard, you generally want to go a bit thicker. The film strength difference is beneficial, and none of us bought our cars for fuel economy, or i don't believe so.

Grant

Grant:
Thanks-I've been looking for the 10W-40 for awhile and could never find it locally.

Regarding the Syntec, have you found any data on how the 2 oils stack up under comparable testing? I've never been able to find data on the specifics on one of them--can't remember which.

Many manufacturers spec things differently. The most important number, to me, is the HTHS (high temp and high speed) shear number. It measure ability to protect (not shear) under high stress and heat. You must exceed 3.6 to pass ACEA A3. M1 0W40 for example, passes by a smidge (<3.7). If you read between the lines i told you much more earlier, but cant reference it. Lets say achieving 3.7 might have required work.M1s own 10w40 high mileage sails through with a 4.1, 15w50 is > 5.

BP lubricants does not say, but all their xw40 grade oils meet A3 without games. Their spec sheets are freely available as PDF with cSt values for all their oils plus API and ACEA certifications.

I also like ELF/total products, castrol edge (if only we could get the 5w40 euro formula here...).

On the other hand, people get way to bent out of shape over small differences. In the winter, when its cold and i don't go to the track, i often throw 5w30 synthetic into the car if need be. Before i studied the details of oil and the byzantine oil marketing stuff, i used M1 5w30 in a turbo car - thinking it was great stuff and i was doing the right thing. 100k miles of turbo-hell later, it was perfect - quiet as a mouse, still using exactly zero oil between changes. Today i would have used a thicker oil to fight off coking at hgih turbo temps, and avoid fouling the oil return line.

Grant

Absolutely, positively, require the use of VI improvers. VI improvers break down - yielding an oil that no longer meets the high temp shear performance suggested by its DC-to_light rating. Worse yet, they can cause film tear in main bearings, and when they do break down, they are a component of sludge.

So i always advocate the narrowest range you need - e.g.:L 10w40 rather than 5w40 and certainly not 0W40.

5w50 is a product of the marketing department, not of chemical engineers. For the record, yes i did ask them :-)

Grant

oil vs. Mobil oils on a rennlist forum not too long ago. (The 997 forum IIRC.)

VI improvers are not needed due to the way the oil is made, because IIRC its base stock is superior to Castrol's etc.

I have given up trying to keep the various oil arguments straight, and have decided to go with/use an oil that is on the most recent Porsche approved oils list I can find. And while Mobil 1 5w-50 is on the list, Castrol Syntec 5w-50 is not. Nor are any 10w-40 oils. Also, FWIW, ZDDP levels are quite high in the Mobil 1 oils and I can't find any ZDDP numbers for the Castrol oils.

For oil questions regarding cars that are in warranty I can only advise one to use an oil approved by Porsche for use in the region and in the climate and for the driving conditions the car experiences. For cars out of warranty the owner is free to use whatever oil he wants but I still advise one stick with an approved oil. A car's oil requirements don't suddenly change at the end of warranty. But of course many owners (and every Porsche engine builder) have their own ideas regarding what is the best oil. Frankly, it probably doesn't matter too much. More important I think is that as long as a quality name brand oil used of the proper grade/viscosity the next most important thing (and maybe the most important thing) is that the oil get changed more often than it does.

Sincerely,

MarcW.

Can't wait to get my 99 Boxster out of its hypernation :-)))

Free Snow Any one?

Did you get it from Advance online? They usually will not include oil in their discounts.

dghii
2000 Boxster S 6speed 112k miles

We dont know all the facts of course. But we do know two things:
1. Mobil's base stock appears to be in the phase of being cost reduced.
Mobil stopped using Group IV base stocks years ago, claiming they were no longer needed. And dancing like crazy in public.
They also have multiple M1 formulations at different price points Gold cap vs Red. etc. Marketing led formulations typically are not exceptional.

2. Longer chains are more viscous and shorter ones less so. Even when the parasitic variations (the original benefit of synthetics was molecular uniformity) are reduced or eliminated, the fact remains that an oil is not truly both 0w and 40w. It just meets the template by vary-ing less with temperature.

Base stock quality allows synthetics to have no VIIs at 5w30 and 10w40 grades. Its nearly miracle. Buy beyond that i am very suspicious, and when i see sludge and shear, i can put two and two together. Empirical evidence argues against that engineer.

Is it awful stuff? No. I'd use it. i did in the 986 for 2? years. But there is better stuff, including Mobil's own. Use 10w40. or mix 50/50 0w40 and 15w50 and have a nice 7.5w45. yes, it does work that way. we've seen results of 0w40 shear down. Its not guaranteed, but its also not debatable under tough conditions.

And its also not debatable that thicker oils hold up better under high temp and hgih pressure. On balance they don't flow as well, but do we need water at or above 10 deg F? Drive easy the first 2 miles- its a far better plan anyway.

Sadly, all the oil companies are moving from engineering to marketing. And all are dealing with OEMs' demands for free fuel economy. Its not hard to see why.

Grant



Edited 1 time(s). Last edit at 02/10/2011 08:05PM by grant. (view changes)

for two reasons.

1. it was introduced in 5w50. See my various rants above about wide ranges and the requisite VIIs. SO the first product out the door had great specs but suspect quality. Sorta like a F458 made by Yugo.

2. The early Syntec did not (reputedly) have the same quality base stock as early Mobil1. But then four things changed. a) mobil1 changed their base stock, and is rather mum on it, but its not to make it more costly. b) castrol improved their base stock. c) Castrol also introduced EDGE with a fabulous base stock ( we don't get the good stuff 5w40 here though) d) castrol changed their additive and formulations so that they have 5w20, 5w30, 10w30, 5w40, 10w40, and 0w50, many of which meet ACEA A3/B4 (high performance shear) and dont need VIIs or need little.

So maybe the "engineer" was not up on the shifting sands.

Grant

I took into account the oil analysis that "Jeff in PA" had seen in his shop and started using the Syntec 10W-40 last year.

So far, my car has not blown up.

Good price for Syntec. I bought my last round of oil from Advance for the same price and had them include filters for my other vehicle. Wally world is usually $6.87/qt and neither the 5W-50 or 10W-40 is available locally in 5 quart containers.

dghii
2000 Boxster S 6speed 112k miles

It as based on recommendations from a lot of guys racing and tracking Porsches. You just have to remember to give the car a proper warm-up/cool-down period. I get a little more lifter noise, but it seems to be holding up well on the track and never smokes anymore.

1998 986 Turbo-Look Cab
172,000 Miles
Dilithium Crystal Supercharger