Reduction of the engine rattle that many 996 turbos exibit.
#16
Burning Brakes
#17
Burning Brakes
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Exactly.
That the noise comes back so quickly highlights just how quickly these supposedly so superior diesel engine oils break down when subjected to the demands the 996 Turbo engine places on its oil.
To make matters worse to gain the temporary peace and quiet the whole of the engine is running this oil.
What perfectly good internal engine oil/bearing interfaces are being sacrificed to quiet down what can only be an abnormal noise?
The noise must be an abnormal noise based on the lengths some owners will go to in a effort to quiet the noise.
An abnormal noise then that almost certainly arises from some mechanical problem -- that may not be that expensive to fix if dealt with early/soon.
A mechanical problem that almost certainly will not get any better over time and in fact will almost certainly get worse, to the point these currently highly favored diesel engine oils can no longer deliver the level of quiet some owners seek.
When that time comes, well, there's always 75w-90 transmission oil. But not a Porsche approved 75w-90 transmission oil. Oh no. Be sure to use a transmission oil approved for diesel truck transmissions.
Sincerely,
Macster.
That the noise comes back so quickly highlights just how quickly these supposedly so superior diesel engine oils break down when subjected to the demands the 996 Turbo engine places on its oil.
To make matters worse to gain the temporary peace and quiet the whole of the engine is running this oil.
What perfectly good internal engine oil/bearing interfaces are being sacrificed to quiet down what can only be an abnormal noise?
The noise must be an abnormal noise based on the lengths some owners will go to in a effort to quiet the noise.
An abnormal noise then that almost certainly arises from some mechanical problem -- that may not be that expensive to fix if dealt with early/soon.
A mechanical problem that almost certainly will not get any better over time and in fact will almost certainly get worse, to the point these currently highly favored diesel engine oils can no longer deliver the level of quiet some owners seek.
When that time comes, well, there's always 75w-90 transmission oil. But not a Porsche approved 75w-90 transmission oil. Oh no. Be sure to use a transmission oil approved for diesel truck transmissions.
Sincerely,
Macster.
Oh, and I use Delvac 1 gear oil in my transaxle as well! Factory fill on the GT cars. If it's good enough for them...
My garage looks like I have a fleet of diesel trucks with all the Delvac products..
#20
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Synth diesel oil will make the noise go away, thats good! But if I can tolerate the rattle with 0W-40 oil, is it just the noise I will deal with or will it have an effect on engine life? I am ok with the noise, I just say to myself its the GT1 race engine, it makes some noise, but if the rattle is breaking down the engine eventually, why on earth they put 0W-40 in the engine at the porsche dealer?
#21
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Exactly.
That the noise comes back so quickly highlights just how quickly these supposedly so superior diesel engine oils break down when subjected to the demands the 996 Turbo engine places on its oil.
To make matters worse to gain the temporary peace and quiet the whole of the engine is running this oil.
What perfectly good internal engine oil/bearing interfaces are being sacrificed to quiet down what can only be an abnormal noise?
The noise must be an abnormal noise based on the lengths some owners will go to in a effort to quiet the noise.
An abnormal noise then that almost certainly arises from some mechanical problem -- that may not be that expensive to fix if dealt with early/soon.
A mechanical problem that almost certainly will not get any better over time and in fact will almost certainly get worse, to the point these currently highly favored diesel engine oils can no longer deliver the level of quiet some owners seek.
When that time comes, well, there's always 75w-90 transmission oil. But not a Porsche approved 75w-90 transmission oil. Oh no. Be sure to use a transmission oil approved for diesel truck transmissions.
Sincerely,
Macster.
That the noise comes back so quickly highlights just how quickly these supposedly so superior diesel engine oils break down when subjected to the demands the 996 Turbo engine places on its oil.
To make matters worse to gain the temporary peace and quiet the whole of the engine is running this oil.
What perfectly good internal engine oil/bearing interfaces are being sacrificed to quiet down what can only be an abnormal noise?
The noise must be an abnormal noise based on the lengths some owners will go to in a effort to quiet the noise.
An abnormal noise then that almost certainly arises from some mechanical problem -- that may not be that expensive to fix if dealt with early/soon.
A mechanical problem that almost certainly will not get any better over time and in fact will almost certainly get worse, to the point these currently highly favored diesel engine oils can no longer deliver the level of quiet some owners seek.
When that time comes, well, there's always 75w-90 transmission oil. But not a Porsche approved 75w-90 transmission oil. Oh no. Be sure to use a transmission oil approved for diesel truck transmissions.
Sincerely,
Macster.
You sir, are a Porsche purist apparently, which is fine
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However, I disagree with your friendly sarcasm, asserting that people are unwise to use something slightly out of the box in their engines. I assure you, that there is no downside to using diesel oil in a high power, turbocharged gasoline engine. New formulations do not harm the cats either. Many, many professionals use it. There must be some logical reason for that fact.
Diesels work much harder, under high pressures and temperatures, and have more interaction with fuel , so they are designed to be very stable in some really ****ty conditions . Granted, diesels do not rev as high, but that is not factor in this scenario. The oil is very very resistant to break down. At least as much as regular oil. I have been using Rotella for years, in modified, high boost turbo engines that we build and service. The reason why we use it, is that often, you have to run modified engines a bit rich, which can cause some fuel to mix with the oil, resulting in lower viscosity that is measurable. Rotella is much less prone to thinning in my experience.
I never used it to quiet an engine that sounds like it's got a bad chain tensioner, nor would I have expected it to do so in my 996 turbo, but it has made a surprising difference when nothing else has. It's not a fix, but more of an aid.. I have never used Delvac, but I will try it..
Additionally, since I now can confirm based on recent experience, that literally every turbo I have listened to make the same noise to some extent, so I don't think it's a problem that will lead to engine failure. Rather,a characteristic of these engines that is not desirable. I am extremely ****, and I notice everything. Every little noise, and every little everything.. And I have always been willing to think out of the box, and listen to others that do as well. You don't know what you don't know, right? I think that is why I have been successful in the automotive repair industry.. There is still plenty I don't know about my new baby , but the information is out there when I need it. You just have to seek it out. This fourum has been extremely helpful.
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Last edited by innovator; 09-15-2011 at 10:37 PM.
#23
Three Wheelin'
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Synth diesel oil will make the noise go away, thats good! But if I can tolerate the rattle with 0W-40 oil, is it just the noise I will deal with or will it have an effect on engine life? I am ok with the noise, I just say to myself its the GT1 race engine, it makes some noise, but if the rattle is breaking down the engine eventually, why on earth they put 0W-40 in the engine at the porsche dealer?
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Synth diesel oil will make the noise go away, thats good! But if I can tolerate the rattle with 0W-40 oil, is it just the noise I will deal with or will it have an effect on engine life? I am ok with the noise, I just say to myself its the GT1 race engine, it makes some noise, but if the rattle is breaking down the engine eventually, why on earth they put 0W-40 in the engine at the porsche dealer?
#25
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Playing the devil's advocate: What if the reduction in the rattle sacrafices something else? Viscocity at higher levels can add strain on moving parts. While they are quieter floating in a thicker medium, is it better? I do believe the guy on here with 300,000 miles has run the recommended 0/40 oil from the start. My Indy mechanic with 30 years of P-car experience including setting up race prep cars and racing himself, does not recommend deviating from the 0/40 M1.
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Playing the devil's advocate: What if the reduction in the rattle sacrafices something else? Viscocity at higher levels can add strain on moving parts. While they are quieter floating in a thicker medium, is it better? I do believe the guy on here with 300,000 miles has run the recommended 0/40 oil from the start. My Indy mechanic with 30 years of P-car experience including setting up race prep cars and racing himself, does not recommend deviating from the 0/40 M1.
Everybody has an opinion. Gotta respect it... That's what makes life more interesting!
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Rotella T and Delvac ESP are both a 5w-40 synthetic, so its viscosity Porsche approved. The additive package is different perhaps, but not in a way that would harm the engine. I've never seen cause it cause any bad effects ever in gasoline engines that rev high, like my RS4. Turbo Diesels need even more protection that our engines, despite the lower RPMS.. They run 15: 1 or higher compression. That's a huge load on the rod bearings and crankshaft bearings. The also have heavy chain drives in many diesels. Like our valve train drives.Their oil needs to keep a strong film adhesion, and shear strength, and Rotella is one of big the favorites among many performance engine shops I work with.. The 996 turbo engine purrs by comparison to Mobil 1 0w-40 or 5w50
Years ago the formulations of diesel oils could be harmful to the catalysts , but that is no longer an issue. Rotella T is safe with cats and gasoline turbo engines..Approved oil ratings are often due to both political/EPA and proprietorial motivations by the auto makers. Keep that in mind..
#27
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I see a bunch of you should be driving a prius. 911, an icon, race car in street clothing it won't be silent. Wow get in smash the pedal, drive and enjoy. Seems like there us a lot of crying about nothing lately. I would love to see the cry babies in an f40 lol. Enjoy your cars you old darts, drive the.
#28
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I meant old farts
#29
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And yet somehow there exists a 2003 996 Turbo with 300,000+ miles using Mobil 1 0W-40.
I have adopted a unique strategy to avoid making the wrong decision on which oil to run.
I simply don't start or drive the car.
I have adopted a unique strategy to avoid making the wrong decision on which oil to run.
I simply don't start or drive the car.
#30
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I would only use the TD oils as long as it has the same API specs as the Porsche gasoline requirement or higher. Not all tubo diesel oils carry the gasoline API rating that Porsche requires! So lets not all make a blanket statement that TD oil of all kinds is okay! It goes beyond viscosity. Both Delavc and Rotella T carry the applicable API's.