DO NOT USE 15W50~~~~~~~~

Switched back to 0w40 and all problems solved. Changed the MAF for good measure and the car is back to normal. Previously installed race cats when car was not running right and it was way out of tune, down on power, and too loud, even for me............ Now that it's generating proper hp, it's not too loud and runs like a banshee. No plans for a tt anytime soon, too much fun. Ordering seats, hood, etc to pull some more pounds................... Still eyeing yellow 355...................

And all these problems are due to oil viscosity because of what?

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Did you get your ECU reprogrammed (or at least wire in an o2 sim) after the Cat-Delete? How did the oil weight affect the car?

I think I'm going to go out and start a paper route right now. Save me up some money for an oil change.

what kind of race cats did you use.. 100 or 200 cell... what brand? did you ever get your error code 1531 fixed... I recall you having a problem on the camshaft actuator bank 1.... dealer resolved?

Sorry for the confusion, this had nothing to do with the new cats. I was referring to the camshaft actuator code and then the sensor code, following with two o2 sensor codes. The oil change seemed to resolve the actuator issue (flat spot above 5k, cam not changing) and sensor issues. Replacing the MAF fixed the other issues...............

what made you want to run 15-50 in the first place?

Let's see......... you change your plugs, replaced a fault ignition coil and put in a new MAF along with changing your oil and you somehow identified the oil as your problem???? An inactive cam actuator will not cause a flat spot at 5000 as the timing change is complete long before that. A bad coil might, as well as bad plugs and, yes, even a bad MAF. What won't cause a flat spot at 5000 rpm is your oil. Next thing you'll be claiming is that your coolant temperature never gets above 200F.

and he'll be blaming his coolant for it!

Mine doesn't....the 0 on 180 year round

Like I said, do not believe the gauge.

If your needle is in the 0, your definitely over 200F. The tick mark to the left of the 8 is 180F. Dead plumb needle is about 195F.

For the oil gauge is it an electronic gauge using a sending unit and wires or a direct reading style with a line fed straight from the engine to the gauge? For the temp gauge is it an electronic gauge using a sensor and wires or a direct reading style using a probe direct to the gauge in P cars?

15w50 did not work well for me or my car. I don't drive it much so that may have contributed. I do know that the car was hitting dead at about 5200 to redline. It also did this after the plug and coil change. I read on here that the actuator could be sticking due to oil so I decided to switch and the problem was solved............... I then changed the MAF. Car is running fine now and power has returned. You can believe it or not, don't really care.................. I was just sharing what happened to me. Replacing the sensors and actuators would be expensive so I was glad not to have to do so.

hmmmmm..... so this is NOT really an oil thread......... man....... no need for popcorns.....can someone still pass the butter?

I want the last 30 seconds of my life back...oh well.

Another oil weight debate ... somebody gonna get hurt real bad.

yes, never use anything heavier than 0W... even though it didn't exist when the car was designed.. and made... and the manual recommends 5W up to 15W....and has nothing to do with viscosity at operating temperature... wait, is this another oil thread? OH GOD PLEASE MAKE IT STOPPP!!!

Where did you find 15/50. I have to use that in my M and the only place I can find it is the at stealer

Park Place Porsche has 15w50 for pretty reasonable prices. do a search on google.

Mobil 1 15/50 is the standard oil for the air cooled cars and is available everywhere. Pep Boys, Autozone.... Are you sure this is the weight you need?

15w50 with no problems for over a year...Take it how you wish...

You know that oil related failures don't happen overnight, right? If you put the wrong oil in your crankcase, it won't explode right away. Nitro glycerine, now that's another story. Or fabric softener. Also Mountain Dew.

If you want to use unfounded logic yet interesting fact, then I think it is safe to say that more 996 engine explosions occur using 0W40 than 15W50 since more 996's that (at least as reported on these message boards) have sucome to engine failures when using the Mobil Water. . It's nice to see that so many are finally waking up and moving away from using 0W40 in their flat six.

At ease, soldier. I'm not taking a side in the oil wars. I was just quibbling with the logic that a year without problems equals 'I'm doing the right thing.' That doesn't apply, here, regardless of what you're doing. Same goes for fuels, coolants, etc. Bad habits take a long time to come back on you. BTW, I think the word you were looking for is 'succumb'.

If 1999 is saying 15 is fine, then why he has the need to rag on 0 or what he refers to Mobil water is somewhat... hypocritical. Both are approved by Porsche, no?

There is nothing wrong with 15w50...Maybe in Canada I wouldnt run it but in my situation, I find 15w50 better than the others. I dont care what Porsche says.... Mobil 1 synthetic has gotten A LOT thinner over the years. There have been tests proving this allthough it has been a while since I went into the subject. It doesnt take a rocket scientist to decipher which oil is appropriate for your situation...And before you bring up the Variocam issue, show me a failure due to oil... Maybe what you mean is that getting you to realize more than a couple of oil weights are sufficient doesn't happen over night.

You are correct Bruce..I should have spelled it correctly.

Well let me change subject a little if I may. How do you, my respected peers, feel about the phosphorous and sulfur(?) numbers going down in the new oils which could/will cause failures. I don't think it's Sulfer, but can't remember the other product that's been reduced in the new "green" oils. I read a thread on it but can't find it now, plus I wanted your opinions.

With that burden of proof, I'd say we could go years before having to read another debate about oil. I can't recall anybody on this forum ever having one.

pat056, It's the zinc and phosophorus levels that are being changed and replaced with other,more advanced anti-wear agents. It is more important than ever to pick an oil from the Porsche approved list as the oils on this list will meet/exceed requirments for Porsche engines. I won't get sucked into another viscosity debate....

I say run whatever oil you want...If you screw somethen up then pay the price!

Thanks! i run Mobile xWx weight But was concerned about what I heard on the zinc. I'm glad to hear they are running other anti wear additives as I worried that going green may make parts wear out faster.

My car can use any oil and never gets to operating temp ..Oh Ya, forgot I let the tow truck do all the work.

No, 15w oil is not on the current list of oils that Porsche recommends for the 996

Then what's up with Gator unless he's a Porsche 911 engineer on their payroll?

I never said it was approved... It was at one point however.

I would defer to the testing that Porsche,Mercedes,Audi,etc. have done and pick an oil from the approved list. It's not a conspiracy! The list has many to choose from,pick your favorite. You can be assured that the oils have the required amounts of various additives . Why would anyone argue with that decision.

Because it's hot as hell in Florida and I like to drive spiritedly

Wrong!!! If you have been following these threads you should know it IS a conspiracy... Surely the oil companies pay millions $$$ to Porsche for the coveted honor of being on their list!! Mobil pays huge money to Porsche to "list" their 0w-40 and they would be "sol" if 15w-50 was approved since they do not even make that produc........errr...hold on a sec........Mobil does make 15w-50. Grrrr Stop confusing me! It IS a conspiracy I say!!! Michael Moore should do a film!! I suggest the title "Porschenhype 0w-40"

Damn it worked last time. What I hate is how AMSOIL has mangaged to hijack every Google search having to do with oil. Sneaky bastards.

Well Ray you caught me! I am actually an Exxon Mobil lobbyist working undercover...with all the Porsche people here if figure I can earn Exxon Mobil another hundred bucks or so!!

Slight little mistake sorry............10/60... I know not even close

5W-50 is back on the latest approved oil list. From TSB 02/07 1701 Overview Of Approved Engine Oils (as of 1984 cars to present). The TSB is dated April 11, 2007

/thread LOL! Good stuff, Loren. Thank you!

Wow, I would have thought this thread would have been answered in one maybe two replies....

What are you kidding? This is a religious topic!

Well it looks like everyone who was bitchin' and moaning about 50w oil can shut up until the next TSB!!

Yeah, but what is "someone" brings up 15 W-50? Then we start this all over again!

Yeah, but what if "someone" brings up 15 -W50? Then we get to start this all over again!

I knew it!!

Well maybe this is good for my Exxon stock but I still use and have always used Castrol 5-50. Now go out and use what you want and I promise not to tell you my oil is better.

OK guys, let's change the subject...I'm outta beer and popcorn.

If we're talking "oil" you gotta come prepared with the BIG movie sized bag!!

Man...you can say that again

And just because of the irony, who is in the anti-15W150 camp, almost 20 years later?

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I switched to it July 2023 and have done 34 track days with much more stable pressures.

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34 track days in a year?! And what brand do you use?

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Yes 34 days in the past 15 months, since I switched. About 25 a year. Motul 300V, I was using the 5w40 before that.

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I'm assuming either one is fine for the street / aggressive street driving as well? I'm in San Antonio - hot climate most of the year. Not a DD.

I don't see why not, especially in a hot climate. I've been running 5w-50 for a few years now and will be moving up to 15w-50 next spring. It's been shown that our engines benefit from a 50 weight oil, especially if you see lower oil pressures or if you drive your car hard (as you should) giving you a stronger film strength as temps go up.

I used Mobil-1 15-50 exclusively for the last ten years or so, prior to switching to Driven DI-50 this year after a motor rebuild. I would probably do 3-5 oil changes a year depending on how many track events I attended. During this time, the car was club raced in PCA and NASA and I instructed at my local HPDEs. It was rarely but occasionally street driven. When I had the motor proactively rebuilt my builder commented that there was normal wear and only a very mild amount of bore scoring. I attribute the very frequent oil changes to the generally healthy state of the motor, as much as the use of 15-50. It did provide a minor increase in oil pressure during track usage, but i did not monitor it in any scientific or data driven manner. I am not advocating anything, just sharing my personal experience.

All car manufacturers recommend the thinnest oil and the longest oil change possible for CAFE points on fuel economy and lower "cost of ownership" advertisements...The Carrera was not built/designed to be the "top of the line" Track Machine... Our engines are not typical wet sump engines, they are Integrated Dry Sump engines. What this means is 40% of the oil volume goes to the heads and 60% oil the volume goes to the crank/rods, the 40% that goes to the heads is "pumped" back to the sump via two scavenge pumps....When tracking or driving very aggressively the oil will heat up and thin out, that makes the oil flow volume increase, that increase in oil flow volume will lower the oil level in the sump due to and there is more oil in the heads that needs to be "pumped back down to the sump.....Using a higher viscosity oil will keep the flow volume from increasing therefore keeping more oil in the sump. The other benefits of the higher viscosity is thinker film strength when the oil gets hotter.. I have all the Test Data to back this up from Track Testing a 140K mile M96 engine and have been preaching 50 weight oil since 2019...and there are other things needed to make a good track weapon, this is just one..