Castrol Syntec Oil
 

Where I live, Mobil 1 is not available. I was looking at buying Castrol Syntec 5w 40 oil for my 2004 986. Is this a good choice? I live in a climate where the temp does not go below 10C and in summer can go as high as 38C.

The 5W-40 is good, but the 10W-40 would be better in the heat.

After what happened to my engine, I'm back to thinking frequency of oil changes might be a little more important than the oil manufacturer. If one of these engines is going to let loose it's usually oil starvation or another unrelated issue not the oil breaking down that causes calamity.

Rene, thyere are HUNDREDS of Porsche approved oils. You should be able to find several in your part of the World. You need to obtain the list and review. A 5W50 oil would be very good in your climate, if you could find one on the list.

+1 for 10W-40.

10w-40 it is then! Anyone has an updated list of the porsche approve oils for the 986? Thanks.

I thought the Porsche approved list was relatively short?

I run Motul 8100 xcess 5w40 every 5k miles or 6 months

I use the 10-40 Castro...live Florida where the weather is always toasty. I think the 0-40 is a perfect cold weather oil...like Germany, where it's more cold than warm.

It's gotta be over 10 pages and more than 200 selections.

It seems that the only porsche approved oils come in the 0w-40 and 5w-40 grades. No mention of the 10w-40 grades. Should i still bit the bullet with the 10w-40?

Take JFPs advice...I've been running 10W40 Castrol Syntec in Chicago's hot summers with great results for years. No clatter on start-up and I change it every 3k miles (once a year).

[QUOTE=rene525d;266545]It seems that the only porsche approved oils come in the 0w-40 and 5w-40 grades. No mention of the 10w-40 grades. QUOTE]

You are correct. Plus, Porsche also approves 5W50 in some brands.

By what measurement? Blackstone UOA's?? Engine tear-down??? Gut feel????

Yeah, he (JFP) has done UOAs on both flavors of Castrol, the results of which apparently point to the 10W-40 being the preferable of the two. Do a search---he's talked about it here a number of times in the past. It's what I've been using for awhile.

We offer all our customers full UOA's as part of their normal annual service package; they get the benefit of a full oil analysis, and we developed a rather large data base of info and several brands of oil, as well as different weights with in a given brand in various models of cars. We have been doing this now for several years.

Over time, we also get to see the impact of these oils on the components when we do normal maintenance on the cars, as well as the occasional tear down when specific repairs require it; which gives us the chance to compare the car's cumulative UOA's with the conditions we find with in the engine. We base our oil recommendations on the culmination of all of this information.

Excellent service to your customers, JFP in PA! I also do UOA's for my Porsches, including gear oil. The reports are very helpful when you start to build data points over many miles and several years worth of reports. Have you ever posted on this Forum any of your UOA's? May I have a link, if you have. Thanks.

But, I'd like to know why JMatta thinks he's "having great results for years". Does he do UOA's on his specific car? Is he extrapolating your data into his car? Just curious about how he measures the results.

[QUOTE=Flavor 987S;266560] Porsche has typically "approved" a variety of products without any specific technical definition as to "Why?" The "N" rated tire is a perfect example; another is the use of a 196 F thermostat; both of which have been demonstrated time and again can be ignored with positive results. Oil weights over the last decade of so have been going towards lighter weights with no apparent rationale. Not that long ago, 10W oils were the "recommended" standard for use in arctic like climates; now 0W oils are the supposed choice for use in southern California or Texas; yet most people do not ask why. If one collects and examines the flow characteristics of various weight oils at low temps, you begin to notice there is not all the large a difference between a 5W oil and a 10W oil when they are cold; so why the big push to low weights, particularly when these light weight oils tend to show a lower ability to "stay in grade" under heat and shear? The answers to lie in the manufacturer’s need to get their CAFE ratings as high as possible. Some time back, the EPA changed the standards by which the OEM's develop their mileage ratings for fuel economy; previously, the OEM's had been allowed to use any oil for the EPA testing, and then the EPA discovered that they were using oils like 0W-5 (or lighter) for the tests to max the mileage, but recommending much heavier oils for normal maintenance. The EPA altered the rules to require that the test be run using the recommended oil weights. Porsche went to 0W-40; Toyota and Honda went to 0W-20, and so on.

Unfortunately, this move has sometime backfired on the OEM's, BMW and Toyota both had to change their oil weight recommendations after a large number of early engine failures pointed out the weight's shortcomings of the very low weight oils. When we saw 0W-40 Mobil 1 oil falling way out of grade after a couple thousand street miles in a "soccer mom" vehicle, we started looking for products that could go 5-7K miles under mixed street and track usage in a M96/97 and still pass muster. 10W-40 oils and particularly the Castrol Syntec did that well, while still allowing use in cold temps with no start up issues.

Just because Porsche “approves” or “recommends” something doesn’t mean they do it with your benefit in mind………..

We have shared data extracted from our data base from time to time on this site and others, but as the total number of data points is rather large, and because our legal advisors point out that the data is actually the intellectual property of our customers (after all, they paid for it) which they have agreed to share with us for limited purposes, we cannot realistically publish it in total without their permission.