gophaster

Maybe this should be made a sticky? Seems this sound startles just about all new owners. I don't blame anyone for asking about it because The Mezger Signature Sound (TMSS , if you will) ...is quite unique.

jungt

This is the noise I am getting when the engine warms up.

Is this similar to what others are experiencing? Sorry for the poor audio.

John

Kevinmacd

Cant get your file, but here is a speedtech exhaust utube sample, when at idle you will hear the rattle, maybe this answers your question.

Gt3stig

i agree, the lower the oil level the quitier the rattle. By lower i mean down to 3/4 full...
M1 5w-40 td oil worked the best for my car to quite it. The oil that made the engine the loudest was Redline 5w-40.

A freind has a 10k mile tt and is still using M1 0w-40 and the car has no rattle.

Kevinmacd

I question that since its a dry sump engine, it gets the same amount of oil until it gets to a very low level below the fill range, which of course is catastrophic!
What does having a lower oil level in the tank have to do with this noise. Think this is evident by the oil pressure being pretty much the same within the acceptable fill range!
As far as these cars go I have not heard one with the mezger engine without it!i It may get more prominent with more miles but its there regardless!

Gt3stig

^^^^Kevin
i know its odd, but that is what I experience.

gophaster

If I ever heard one without the sound I would be fearful that the car may have had it's engine swapped for an ordinary production engine...couldn't resist, lol

gophaster

I was able to download the vid to my phone and watch it on VLC app. A little hard to tell in a vid with 100% certainty but it sounds like the Mezger sound to me. You should upload the vid to youtube and post link so others can chime in.

"02996ttx50

^ fully agree. jungt, from where i sit and taking into account a lousy cell phone audio file, the car sounds well within the range of "normal" to me!

also, to the previous posters claim that running with the oil level at 3/4 or running a heavier viscosity resulting in less? of our timing chain rattle? this runs opposite and contrary to my personal experience.

my car runs the most quietly, by running the 5/50 ( heavier ) and as close to the upper oil quantity limit ( full ) as it can be.

not sure how a thinner ( 0/40 ) oil will ever result in our motors being "quieter" than they will by using a 5/40 or even a 5/50.

Kevin

The 996TT engine rattle and decibel noise level is subjective.. And yes there is NO rhime or reason between engines/cars..

What does work to quiet the engine is running a 5W40 or 5W50 and/or a blend.

Please note: all of the Diesel Heavy duty engine oil formulations have changed. Results will vary. I am not using TDT or Rotella anymore and have not reviewed any UOA reports.

Interesting previous engines like the 964 (different crank, 930 rods) and 993 and 993TT (same crank, rods)share the very same bottom end components. Crankshaft, rods, bearings, similar IMS, and oil pump.. These engines ran on 15W and 20 weight oils.. I don't recommend using those weights with the vanos/variocam plus system but you can see why the heavier weights "work"

Orphan

John ,,
Your engine sounds fine to me.
My idle is very quiet ,, I only get the rattle after the engine has warmed up (80C on the Temp gauge) and only, when I rev up between 1,800 and 2,000 RPM. Usually 20 minutes after I have begun driving.
Trust me ,, I had exhausts pulled to check the heat shield,, had an INDY tell me it was oil pump .. Porsche tells me it was fine another INDY said my CAT was blown ,,, another the chain.

Enjoy the noise ,,

Orphan

Kevin,,
Doing a DD reading your posts, on 5-50 oil convinced me. I buy Mob 1 5-50W online at USD 9.50 a liter and do the DIY oil change, in my garage. Or take it to the shop, for USD 25 charge. All the filters and washers comes, from Pelican.

Daytonaman

After using Motul 300v 20w60, the rattle was still present. Thought it was normal.
Then switched to Rotella T6 5w40, engine was considerably quieter, even after warmup.
It seems some have had better results with Mobil 5-50.
If the T6 has been reformulated, then it will me Mobil 1 next service.
It would seem heavier oil did not prevent "slop" in the gear-chain train, but is related to additives.
@350 degrees, even 90w thins out.

rosros

Before I purchased my car, Napleton Porsche did a ppi and the car was declared a good purchase. When I first heard the noise I was worried: thinking the Porsche tech missed the noise during the ppi. The car had spark plugs changed so I though maybe the plugs loosened up. I called the shop and asked him about it. Immediately he said chain tensioner, not to worry.

The worse noise is upon first start up, the marble sound.

Macster

20w-60 oil has lots of viscosity improvers which break down over time.

It is asking any engine oil too much to affect gear lash noise which is where the bulk of the Turbo engine noise comes from.

Also, you can't go by what some report regarding engine noise. Some engines are going to be quieter or noisier than others mainly due to manufacturing tolerance differences.

Mobil 0w-40 actually has a higher Viscosity Index (VI): 185; than 5w-50 which has a VI of 180.

A lower number means a greater change with a change temperature. This suggests to me the desire is to get that "50" to drop a bit closer to "40" when the oil is hot.

This makes some sense as the bearing clearances are primarily what factors into the upper viscosity number. Street engines run pretty tight -- relatively speaking -- bearing clearances as this makes for a quieter running engine that doesn't have as large an oil budget as one with looser bearing clearances.

However, 5w-50 has a higher HTHS number: 4.4 compared to 0w-40 with 3.8.
5w-50 oil is a bit more resistant to flow in the narrow confines of the bearings than 0w-40.

Run 5w-50 for a bit better protection from high temperature high sheer (load) break down. But it won't really help stifle layshaft gear clatter or soften the noise from the chains.

After runing 0w-40 for hundreds of thousands of miles in my Boxster and over 130K miles in my Turbo, with either car I can't tell the difference between 0w-40 and 5w-50 oil from how the engine cranks when cold, how it sounds at cold start and during cold idle, how it sounds at hot idle or at any RPMs up to redline.

Even with the Turbo having an oil pressure gage the hot idle oil pressure behavior is the same with either oil in the engine. On a cold/cool to mild day the hot idle oil pressure is 2.0 bar. On a warmer day or with low speed and high(er) RPMs such as driving in town where I accelerate up to maybe 30mph then have to come to a stop a short time later for a stop sign or stop light the hot idle oil pressure drops a skosh under 2.0 bar. The engine/the oil gets hotter under these conditions.

Also, I can tell you both engines quiet down a noticable amount after an oil change. This is normal.

How quiet is kind of impressive. I had the Boxster in for an oil change the other day and to have the tech diagnose the source of a noise from what I suspected was a problem with the accessory drive system. In trying to reproduce the noise I took the car and drove it around town for 30 minutes to get the engine nice and warm and reproduce the noise for the tech. I even left the car parked on the service drive with the engine idling when I went back to speak to the tech about my lack of success in getting the noise to appear. After a few minutes I returned to the car and couldn't hear the engine. At first I thought it had stalled. But as I walked towards the back of the car I then heard the exhaust. The engine was that quiet after an oil change. And with almost 310K miles on it too.

(Oh the noise... Tech reported the belt was fine, none of the accessory drives exhibited any bearing slop, no signs of any belt contact with the sides of any pulley, all the idler roller bearings and the tensioner roller bearing were just fine. No signs of any leakage at the water pump. The tech (and the SA) told me they get maybe 5 or 6 cars in a year with something similar and it proves to be something getting blown up -- paper or a leaf maybe, or sometimes water splash if the roadways are wet -- and into the belt.)

Anyhow, both engines quiet down after an oil change to be sure, but also to be sure both are rather noisy again especially after 5K miles.

At the suggestion of several Porsche techs I have been using Swepco 502 oil improver, 2 bottles in each engine. Senior Porsche techs have recommended using this oil improver to help quiet engines that aren't used often. Mine are used very regularly and frequently, pretty much I alternate between the two cars every other day. But I added two bottles to the Boxster after an oil change and 2 bottles to the Turbo after an oil change and both engines got a bit -- just a bit -- quieter.

Try 2 bottles of Swepco or don't. Up to you.

Regardless of what you do the Turbo is never going to be as quiet as the Boxster engine, or the 996 NA engine, or any number of other engines either. It is a high performance engine and these are by nature noisier than lower performance engines.