Kevin

OS, this is NOT the same engine with the broken chain

Last 930, The oil filter, IMS, chains, and most of the bearings were forwarded to the aftermarket insurance company adjuster. With that said, I do have a few filters packed with metal. I'll try to take a few pictures.

Simi 911, I would recommend using the Mobil 5W40 TDT, and when you reach 500 miles change the oil filter and look at the metal content. Check to see if you have metalic debris or aluminum. Do you have alot of chain noise? The metal content will increase to a point where it packs the filter. The noise in the bottom end really increase.

I have received alot of emails from this thread>> If you have a loud IMS spend some extra time chainging out your oil filter and checking for metal. There isn't a rule against installing a NEW oil filter every 2000 miles.

Kevin

I would be very careful about adding oil additives.

Typically you have 4 different oil additives on the market.

1) ZDDP is the major anti wear additive that has been restricted due to emission issues with the Cats. There are aftermarket zinc additives that you can buy like ZDDPlus and GM's EOS assembly lube and STP.

2) Chlorinated Parifin, which is a very good metal conditioner>typically used for gear sets and gearboxes. There is a HIGH content of CF in Castrol 10W60. I have used this in different applications over the years. Aftermarket suppliers are Energy Release. Please note that this is some VERY nasty stuff. The metal to metal conditioning is a the TOP of the scale. I use a blend of this product for my turbocharger assy lube> My special BLEND...

3) Moly based additives, there are many Moly based lubes. I tend to favor the LubiMoly brand. With that said, I would use ZDDP or CP before Moly based lubes.

4) Teflon based lubricants. This was very popular 15 years ago. Fram use to manufacture oil filters with Teflon added as a pre-lube engine additive. I don't recommend this additive...

If going to the dark side of additives, you have to be very careful which additive the chemistry of your engine oil "base" is. You can run into trouble running CP with a ZDDP based Mobil 1. However, I personally feel that CP is used in the Mobil 1 TDT for the gear to gear conditioning. It's just my opinion.

I have the old HIGH content GM EOS on my shelves that I hord for special engine projects.

LVDell

Kevin, thanks again for all the input. It is much appreciated

haulinkraut

Kevin,
Do you think 5w40 would have saved the IMS bearings? Are the IMS bolts stretch type bolts? Have you ever seen this happen before and if so do you think the harmonics from the bad bearings were the cause there too?

I know it is alot of ?s, but I think the more info will help people from being afraid to drive their 996TTs because the engine may blow up. I think the forum environment is always difficult to read because when a engine builder posts pictures of 996TT engines with issues like this, people rarely realize that you(engine builder) usually crack these engines open for repair work. That means the sample info shared is of engines with issues. It isn't often somebody just opens one of these up to look unless an issue is suspected. So the paranoia af a large engine rebuild gets sensationalized from all the posts on engines that have these types of issues. If you crack open an engine just for a rod replacement and nothing else, how many of those do you find surprises like this?

The bottom line is I know these engines are not invincible, but they are not made out of egg shells either. FWIW I take your advise very seriously to avoid repair bills like this, but I am not afraid to drive this car either. I have since switched to 5w40 TD M1 per your advice and the engine noise is much quieter. I think people here need to take your advice seriously and also realize that not everyone with a 996TT is sitting on a time bomb engine. I really appreciate all the sharing of info you do here, Kevin.

Kevin

I have written in previous threads that I feel that there is to much load>drag>placed on the factory IMS drive gear and crankshaft nose gear. I have seen the "key" wobble out of the crankshaft keyway. I have also seen the IMS chain gear KEYWAY opened up where you have excessive wear.

I also feel that there is NOT enough oil supply to address the oiling issue of the bearing surface. On engines that I am working on, I will take measures that will address this.

I think that IF one can do everything in his power to provide better lubrication and cleaner oil thru oil MORE frequent oil changes the damage will be kept at bay.

NOT every engine fails.. But we can't stick our heads in the sand either.

Folks, I supply crate Porsche engines to folks that have failed engines. It is a process to work with aftermarket insurance companies, and many times a check has to be written for a new engine. I get the cores back to tear down. I have two engine cores just sitting that need to be torn down that have IMS failures>issues.

I personally feel that 0W40 isn't cutting it for long term owner. That is my opinion. I'm not running 0W40 in any of my engines. Nor am I filling any of my customer engines with it.

Edit > there is differing views with regards to the bolts. In Europe my friends feel that the bolts aren't strong enough to use a higher "torque" value. This can be fixed by installing higher grade bolts and installing the earlier locking clips to prevent them from backing out. I personally think that there is to much shaft motion and flex that is causing a shaft imbalance. A imbalanced rotating object will shake anything loose over time. The best cure is using the 959 IMS.. A very expensive piece of hardware!

whiteturbo

I have always used the Mobil 0-40 so you are saying the 05-40 is the better of the two. I have never liked the thought of using the 0-40 but because Porsche recommends it I have used it. Maybe it is time for a change.

ltc

IIRC and AFAIK, perhaps the highest mileage, New England 4 season daily driver, 03X50 996 Turbo, almost 300k miles, has run M1 0W-40 since new...FWIW.

Kevin

Lewis, there are only a handful of these high mileage examples that we hear of. I can tell you that I have more that 3 to 1 ratio of "crapped out" vs high mileage engines.

I recommend Mobil 1 5W50 Mobil 1 5W40 TDT if you have IMS noise, and Motul 300V. All of these oil over M1 0W40..

pwarnery

Hi Kevin,

what about 5W50 Castrol Syntech, easier to find in CA?

Kevin

http://www.mobiloil.com/USA-English/...duct_Guide.pdf

For Air-cooled turbo owners>> look at the Mobil 1 Vtwin

996TT and 997TT owners look at the 5W40 Turbo Diesel Truck

Look at the Racing oil levels..

LVDell

If somebody can point me to an explanation (if somebody has posted one) of the differences between the Regular Mobil1 and TDT I would appreciate it. I am having a hard time wrapping my brain around using a TDT in a petrol engine.

Here is from the link Kevin just posted. (thanks again Kevin!)

Kevin

All we care about is the API rating which tells us that it is also rated for Gasoline engines.. We are wanting the higher ZDDP levels.

LVDell

Ah, that makes more sense. Thanks for clarifying that Kevin

puma

Kevin, i am confused, i don't think i have the IMS noise but i have always put 5w40 diesel in it.

Are you sayin 5w50 is better and go to 5w40tdt if you have IMS noise?

Man i love these threads, thanks for your time Kevin, you are still the one who has my business.

puma

hmm well i just read the other thread and it seems like 5w50 is the way you suggest but you usually tell those in hot climate that this oil is the one, what about us in Canada, you know the climate here right