The racers edge. You are right on. A thin oil lets the engine rev faster. You just need to change the oil more frequently. I like 0-30W or 5-30W for a fast reving engine and change the oil and filter every 1000 miles.

 

Thanks for the replies - lots of variation.

 

Just to throw my lot in,

I ran 15w 60 Castrol RS in my Cosworth Rally Car is a 1.9 ltr 120cui 4 cylinder produced 500 bhp and 500ft lbs torque. That's a stressed engine and did very well in competition. The engine cost about as much as a stock 996tt complete engine so you can see it was a bit trick.
If i ran it on the Ford recommended 10w40 I had an oil light and low pressure when idle at the end of the special stage.
Factors to think about are:
What is the environmental temperature ranges in your area
How hot is the engine going to get.
How stressed is the engine.

Porsche have already done this and have made their recommendation.
For road use why would you go against their advise.
However for all the super modded cars producing much more heat and stress the type of oil might have to be looked at.

Now think on this.

My engine was as as much a Race pedigree Engine as any 996tt engine. Its is bored out with much more clearance than standard. When racing pistons get hot they expand. At this level of power to given engine size my pistons are going to expand a lot. You don't want them to seize in the bores so they are designed to be a little too small for the bores when cold.( talking thou's of inch) Oil consumption is very poor until the engine has warmed up correctly.
Main bearing clearances are honed for very hot metal, thin oil Pi**e's out if too thin giving low oil pressure. For my example 15w/60 was the correct type of oil for my racing engine. Ford uk do not produce a factory car that has this power so their standard answer is use recommended specification oil.

So its a bit complicated. Horses for courses. If you race your 996tt and have very high power loads you have to make a decision as to the oil used.
If you run a standard 996tt, Porsche have done it for you.

Frank.

 

I tend to do a few miles at a weekend, then the car stands for a week when I'm at work -It doesnt get thrashed. Am I therefore using the car at its worst for oil consumption?

 

who knows. Do you have oil pressure issues. A highly modded 996tt i suppose will still have the basic components in it. If you don't thrash it, perhaps you should stick with what Porsche Advocate.
The problem I had with my Race/Rally car is that on stage it gets thrashed and I mean thrashed. 15 miles on country lanes/roads or forest. Then you might have to drive 40 miles on public roads to get to the start of the next special stage at legal speeds.The engine is cooking for 10/15 minutes then cools down for another 30/40 minutes. You have choose the oil that will satisfy both jobs.

 

Here is my .02. Their are alot of factors to effect oil consumption. I know some people in the B5 S4 community have been experimenting aith oil types and weights by doing blackstone analysis on the different oils to guage the wear. Some people run 0w in the winter so the oil doesn't flow as well until it gets hot and can cause oil starvation. Personally I would switch to a different brand of oil before I changed the weight or viscosity. The formula that Mobile 1 uses is different now than it was when the 996tt engine was developed. I had issues with a noisy valvetrain on my S4 with Mobile 1. Those noises went away when I switched to Castrol Synthetic of the same weight and viscosity. Elf and Pentosin make a good oil and I know quite a few mechanics that swear by it. I would be hesitant to switch weights on the oil on the 996tt. Maybe an engine builder can provide a bit of experience on this.

 

Sunnyside- no issues at all, pressure excellent, no noise, pulls really hard. It just seems to use more than Ive ever known in a car. Still within Porsche limits and for the miles I do a year it doesnt really matter - Plus if I drop the oil every year as most recommend does it matter if it ends up coming out the back or dropping into a bucket on the garage floor?

The thread was really to establish what people are using for a variety of reasons.

I have read that Mobil 1 ow40 isnt what it used to be ? and therefore not now necessarily the best oil for the TT. Everything moves on ?!

That 5w does last a bit longer and 15w longer still. There seems to be more people using 5w than anything else.

Some very reputable people have suggested other brands are now a better choice for the 996tt engine

All in all Im not much further on as ther seems to be a lot of variation of opinion. I perhaps had thought most would say one brand or viscocity at least.

Its a bit like asking what turbo should I change to?

 

On my 996tt I run any oil that complies with Porsche specifications. note here in Scotland it seldom goes above 22 dec C and in winter averages at about 3 deg C . Last winter was -9 deg C for 2 months. I would hope Porsche have taken these sort of weather conditions into account with their choice of oil.

Just a quick add on.
Over here Mobil 1 have brought out another oil, haven't looked into it but its got a different viscosity? Have you got this new oil out there. Also I would say your correct, if the original Mobil 1 is still so good, why have they brought out a newer oil. I will find out what is is sold over here as and post pack.
Frank

 

It would seem we have these Mobil One products:

Mobil 1 MS 15W/50 5L

Mobil 1 ESP 5W/30 4L

Mobil 1 New Life 0W/40 Oil 5L

Mobil 1 ESP 5W30 5L Fully Synthetic Engine Oil

There used to be a time when Mobil 1 was the only 1. Now it gets a bit confusing which to use. I still use the original.......for now lol

 

Think Ill stay with Mobil1 and maybe try slightly thicker - see if I notice any difference.

 

John,

Reading the posts to find your mileage and how much oil you use I realised your also form the UK . Sorry about that thought you were States Side.

How Much Oil do you use and what is the mileage of your motor?

Its not just worn or loose engines that use oil. Some times good engines that have had a good hone done can use more oil, they just take a lot longer to run in.
A hone is a run up and down the cylinder with a tool that puts a micro size cross hatched diamond shaped cut on the surface of the bore. It looks polished but it isn't.
Why you might ask....it removes any high spots on the bore, cleans the bore of any deposits( de-glaze) and finally and most importantly produces those pockets and as the word pocket suggests they are. Oil is retained in the pockets and makes sure the bores are lubricated. Apart from many other things when you run your car in you are polishing the rough tops off the diamond pockets. If your engine had had a deeper than norm hone it will use more oil. Most times after run in this improves.
I like to see a really good hone. its going to last and is going to protect your pistons and bores better.
Frank.

 

F1 engines tend to be in need of a rebuild every couple of 1.000 km's...

If max. horsepower is what you want (and you can give a rat's *** about longlivety): 0W30 is the best.

If you drive your TT on public roads: 0W40 is fine and if you are still in Porsche warranty I would recommend Mobil 1.

If you drive on closed circuits (DE events, Nordschleife, whatever): I would strongly recommend Castrol TWS 10W60 (sold in different names nowadays, so look for BMW M approval). If your car is still in Porsche warranty Mobil 1 5W50 is a decent alternative.

The reason for choosing a thicker oil is found in higher oil temperatures while racing. I recommend TWS because it is one of the best (if not the best) oils for these applications, because it can handle a lot of stress (the oilfilm will only "break" on extreme pressures).

It is because of this feature that BMW insists on the use of TWS for M models...

However, if you would like to "win" a tenth per lap and don't care about longlivety, please do use 0W30... or even a thinner oil.

(and yes, I know that Shell, that started the quest for thinner oils in F1, found hardly any extra wear when they started to use these thinner oils... but you simply cannot compare a F1 engine to a street engine... build and used for different purposes... Porsche won't give you a 19.500 rpm engine because of the same reason: sure it will be powerfull, but nobody will accept a rebuild after 2K)

 

Car is an 02 with 58k miles. Not sure how much I use. Its done about 1k miles this year since hibernation and I ve just had to add another 1 litre of Mobil1.

No track use, just weekend toy. It sometimes stands all week then does a couple of hundred mile at the weekend in short 25mile or so bursts.

It doesnt leak anything - doesnt smoke and seems healthy.

It just seems to like oil.

PS Would worn out turbos effect the consumption to any real extent?

 

Does your car ever warm up properly. It is best to judge oil consumption on a good run not short blasts. My 996tt uses more oil on a high rev blast. If its within Porsche limits don't worry.
Yes worn turbos can allow more oil usage but you would more than likely see some smoke at idle and start up. If you were pumping oil into the boost side hoses you would more than likely know by now and that wouldn't account for litres of oil over a long period.
I was almost tempted to use the slightly thicker Mobile 1. Let me know how you fair with it.
Frank.

 

there's a big split in the 996tt community when it comes to this oil issue. was frustrating for me as well when I was looking into it. i live in really a hot climate, significant power increase, and push the limits of the engine almost every time it's driven so that's the angle from which my choice was made.

1litre per 1000miles is good compared to avg. i think. of course a lot depends on how it's driven, higher temps/pressures, more oil loss as frank's explained.

if your car is standard or standardish, and you don't ring it's neck to redline often, and since you're located in relatively cool climates, if it were me, would just stick to manufacturer recommended weights.

dont be alarmed if a puff of white smoke comes out at start up that does not linger. This is pretty common for this car. idling the car for few minutes or taking it easy just before destination allowing oil to cool off helps with the start up smoke.