Michael-Dallas

There's also misnomer about BMW oil service intervals. The oil counter starts at 15k, but adjusts itself based on various operating parameters. My old E46 M3 started at 15k, but usually ended up at 11-12k oil intervals. And as it looks, our X5 will get it's first oil change at 11k.

BTW, Porsche's recommendation for 996 Turbo oil changes are 12k or every 2 years and not 15k. Check Porscheusa.com. If your car has power mods or sees the track, then I would not follow this schedule.

Michael.

Dock

Then they have changed the mileage (and that's fine), because at least the '02 Turbo's maintenance manual specifies 15k/2yr maximum.

Danyol

[QUOTE=Kevin;8102787]

I wish that a Mobil oil engineer jumped on this forum. The first thing that I would ask him is WHY does the 5W40 Turbo Diesel Truck knock down the metalic engine noise better than other Mobil 1 oils?

Kevin, I've ran 5W50 Turbo Diesel stuff and now the "5W50"; have you noticed any difference in the two?

doubleurx

I know it was full synthetic at the dealership with intervals of oil and filter at 15,000 miles. I will find out the other items with the exception of "how it was driven" as that is not very subjective or possible to verify as well as when the sludge began to appear. Really that would be difficult as well.

PAULUNM

[QUOTE=Danyol;8109292]The 5w40 TDT really quiets down the motor at idle. The 5w50 I ran sounded just as bad as the 0w40 that was in the car when I bought it. The M1 0w40 and 5w50 have the same zinc and phosphorus ppm, whereas the TDT 5w40 has more ZDDP additive package.

Kevin recommends both the 5w40 TDT and M1 5w50- but because my chain/gear noise is so much quieter at idle- I'm sticking with the TDT. I may try Delvac 1 5w40 after I run the TDT for 3k miles- then have a UOA done on that oil as well.

All I can say is- LOL @ 12 or 15k intervals. Don't buy a used sliver TT out of Atlanta with extended oil change intervals!

Dock

A few points...the Porsche recommended oil/filter change interval is not an "extended" interval, it is their recommended maximum interval; no one will ever have look for my Polar Silver Turbo for sale, because I'm never going to sell it; and the way I drive my car, the 2 year interval becomes the maximum oil/filter change interval. I changed my oil/filter last September, and since then I've put 2100 miles on the car.

Kevin

Danyol, the M1 5W50 is a great oil and recommended over the 0W40. However, there is a miracle or magic snake oil additive in the 5W40 Turbo Diesel Truck formulation that is reducing the engine gear/chain noise.

Either oil is a better choice over the 0W40. Especially for someone living south of the Mason Dixon line.

Danyol

Paul, Thanks for sharing, I thought the same on noise but couldn't say for sure. I certainly notice a little higher oil pressure when hot on the 5w50. I have a sample of the TDT to send to Blackstone from my last change, it could be interesting.

PAULUNM

You know, I didn't pay much attention to the oil pressures- although I should have...

The lack of rattle coming from the motor means I will stick with the Diesel oil, in one form or another (M1 TDT or Delvac 1 since I found a local supplier)...

PAULUNM

Well, it's certainly "extended" compared to what I'm (or Kevin- he builds motors...) comfortable with.

IIRC, Porsche wants oil changed every 12 months if you don't hit their mile limit for an oil change.

Ok- I'm done arguing!

Dock

I have an '02 Turbo (that I ordered new). The maintenance manual that came with the car states on page 9 under "Yearly maintenance"....

"On vehicles which are driven less than 9000 miles/15000 km yearly, a yearly maintenance must be performed."

To find out what a "yearly maintenance" entails, you have to look under section "II. Required maintenance and Lubrication Service" on page 8 under "Yearly Maintenance intended for vehicles which accumulate low yearly mileage between required service intervals". Guess what. There is no mention at all about doing an oil/filter change during the "yearly maintenance". So to find out what Porsche recommends with regard to oil/filter changes on cars that accumulate low yearly mileage you have to look back on page 9, where it states...

"A scheduled maintenance with oil-filter change must be performed after 2 years at the latest, unless the mileage for a scheduled major maintenance is reached earlier".

To know what this "mileage for a scheduled major maintenance" is, you have to look on page 4 under "I. Required for the Emission Control System", where the first item listed is "Maintenance every 15,000 miles/24,000 km", and below this it states...

"Change engine oil"

Notice that in fact it does not specify that the filter must also be changed at the 15,000 mile mark, just the oil. The first time Porsche mentions the oil filter with regard to mileage is under the "Maintenance every 30,000 miles /48,000 km" section (which is also under the "I. Required for the Emission Control System"), where it state...

"Change engine oil and oil filter"

So the bottom line is that the '02 Turbo maintenance manual recommends the oil be changed at no more than 2 year intervals unless there is a mileage trigger reached first.

Kevin

Guys, we have to keep the love.. Cr@p it's only a car. In the end it's your choice. It's like picking a wife. When you have to purchase a used Turbo, spend some time going over the facts and look at how it was maintained. If the car had a rough previous life, you will pay for it in the long run.

NewYorkBuck

If I could interject, I have a lot of experience w TDT as my daily driver is a VW Jetta TDI. Since its a PD engine, VW had a rather archaic "505.01" requirement for these cars, which I religiously followed while the car was under warranty. That said, as these cars started to accumulate miles around 80k or so, problems with cam wear started to show on more than a few cars. The blame as it applies to oil seems to fall on two reasons - 1) the 505.01 standard changing viscosity from 5W-40 to 5W-30 on many oils, and 2) A lack of enough zinc to preserve an additive barrier for the cam and the flat tappets. As a solution, many guys (this one included) have switched to TDT with seemingly good results, even though TDT is NOT 505.01 approved. Some go even a step further by adding additional PoS2 (phos) and ZDDP (zn) as extra insurance. (Me as well.)

All that said, it seems that TDT would aslo be a good choice for cars as well - if TDT can handle the stresses of diesel injectors in a PD engine, then it surely can help our intermediate shaft bearings. I have decided to switch to TDT in my Porsche now as well, with Kevins and Pauls experiences pushing me along quite a bit. Since I just changed my oil a few months ago and its winter in the NY metro, Ill wait till spring to get the TDT in. In an effort to help my 0W-40 in the right direction, I've also added a bit of ZDDP. Non scientific evidence tells me that my engine is a bit quiter since I have, which would be consistent with the higher zinc levels in the quieter TDT oil. Will be nice to buy an oil that is better for my car at a cheaper price as well.

One thing to take from this story is that manufacturers initial oil recommendations may not actually be in the engines best interest. Guys who ignored VWs 505.01 from jump and instead ran Delvac 1 where at first burned on the VW boards, but in fact are laughing last as their cams seem to be just fine.

PAULUNM

[QUOTE=

All that said, it seems that TDT would aslo be a good choice for cars as well - if TDT can handle the stresses of diesel injectors in a PD engine, then it surely can help our intermediate shaft bearings. I have decided to switch to TDT in my Porsche now as well, with Kevins and Pauls experiences pushing me along quite a bit. Since I just changed my oil a few months ago and its winter in the NY metro, Ill wait till spring to get the TDT in. In an effort to help my 0W-40 in the right direction, I've also added a bit of ZDDP. Non scientific evidence tells me that my engine is a bit quiter since I have, which would be consistent with the higher zinc levels in the quieter TDT oil. Will be nice to buy an oil that is better for my car at a cheaper price as well.

[/QUOTE]

You made me blush by saying Kevin and Paul's experience! I'm really just listening to Kevin- with his reputation I figure I can't afford not to! I've never had a motor apart- so I have to leave knowledge like that to an expert.

I also have a 2006 GTI, and cam wear is an issue in that motor (I didn't know the TDIs had that issue as well). I've decided to run Delvac 1 in that car going forward (hopefully not too late). A lot of these modern motors seem to be really hard on oil- even synthetics...

adam_

Right.

But with certainty I **can** tell you that keeping shorter change intervals and using the right oil will reduce the risk of lubrication related failures.

Until people start running used oil analyses and determining what their wear metals look like (and the different metal signatures can tell you where wear is occurring) and looking at the residual oil properties (viscosity, TBN) then conversations like this are just mental masturbation.

Enjoy.

A