06 golf tdi oil change interval questions?

Hey guys just picked up a golf tdi. Great car good fuel milage but I was reading on a tdi forums that the oil change interval is 10k miles. I think that's pretty high? I have always changed my tacoma oil at 5k is there any truth to this post by a guy in tdiclub.com. Here is his post sorry it's pretty long


The problem is WHAT YOU ARE missing by changing oil earlier not to mention being obvlivious to how modern oils protect an engine!

New oil is EXTREMELY aggressive at cleaning an engine out due to one of the components of the "Dispersent" package. A dispersent package can be broken down into two distinctly functioning components, the "Detergent" and the "Dispersent".

The Detergent is burned off over the course of the first 1000-3000 miles as a function of heat and time. This is a good thing becasue these interfere with the placement of the High Pressure wear additives THAT REDUCE ENGINE WEAR!

The problem is these detergents prevent the bonding of the high pressure wear additives that protect the cam, lifters, wrist pins, piston skirts etc because of the cleansing process that is involved to pull residual deposits from the previous oil change into suspension and be held their by the dispersents.

The Dispersent remains effective from mile 1 in the oil thru the life of the oil and prevent conglomeration of the combusion by-products and wear metals. These also prevent the fomation of sludge and other deposits that could form without their presence.

Dispersents in diesel oils are tested out ot 8% and then run for 500 hours at that level to insure protection to the motor and prevention of deposit formation. One of the focus particles is soot, these oils at 8% soot must prove that NO INCREASE IN WEAR occurs beyond an EXTREMELY low measured rate. In contrast, a TDI run for 30,000 miles will at most hit 2% soot...or 1/4 of the oils rated maximum without concern for an increase in wear.

High pressure wear additives are deposited thru repetition, heat and pressure and in the absense of detergents that prevent a bond from occuring with the surfaces.

Every one of these processes are easily documented by frequent sampling e.g. 100 mile oil samples. You can plot the rapid build up in wear metals during the first 3000 miles using a PPM/1K formula. Then after the first 3000 miles the wear rates plumit to near zero! Why? Simple, the detergents are used up and the high pressure wear additives are now providing the sacrificial layers that STOP the wear from occuring. These layers are worn away and replaced over the life of the oil. Even after 30,000 miles you seldom see less than a 10% reduction in these components in an oil sample. You never want to see a significant reduction since the total composition of a unit of oil is often less than 5% by volume of additives other than the oil base-stock.

As has been documented hundreds if not 1,000's of times wear rates are LOWER AT 20,000 MILES THAN IN THE FIRST 3000 MILES INTO AN OIL CHANGE!

Acid, Get over it, acid is no longer a player why? There is no sulfur in the fuel to cause ACID ie Corrosion! TBN which is a measure of the base additive to neutralize acid has been reduced about 50% from where it was when we were running 500ppm sulfur fuels. Keep in mind that we are now at 8-10ppm nominal! And no pump in the US has anything close to 15ppm since this is the MAXIMUM alowed, all diesel fuel MUST come in at 8-10ppm to allow for cross contamination in the pipe-line to prevent exceeding 15ppm at the pump.

What does this mean, simple we have about 500% more base additive than is required to properly treat ULSD operated engines from acid formation over the course of an extended drain interval of 75,000 miles.

With these oils the typical wear particle comes in at 50-500 nanometers, the oil filter can only stop particles in teh 7 micron range with at best a 95% capture rate.

Soot, is in the 50-200 nanometer range thanks to the dispersents. Again no soot can be captured or removed from the oil by the oil filter, not even a by-pass filter can remove this soot assuming 1 micron and 99.9% effectivity.

What does this mean? Simple over time the oil will THICKEN, diesel oils NEVER thin out, they always THICKEN over time. Eventually the oil thickens to the point that you start suffering higher pumping losses. But thanks to the EXTREMELY small size of the particles suspended and the relatively LOW concentration of them, the oil will reach a maximum "realistic" viscosity range long before you see an increase in engine wear. In fact, the wear will actually be lowered by virtue of this visocity increase in the Cam, lifter and bearing regions due to thicker oil layers and slower moving oil films they will support greater loads and prevent wear.

This is why VW often spec's a 5w30 for their long drain oils. When new these oils are HORRID at reducing wear, however 20,000 miles into the change the viscosity is back in the 5w40/10w40 range and providing a nice average wear rate over 30,0000 miles comparable to a 5w40 run for 20,000 miles.

In my opinion, the best (lowest) wear occurs on engines running a 5w40 for 20,000 mile intervals bar none. Unless you plan on running 30,000 mile drains AVOID the 5w30 especially if you plan on changing the oil more often, the increased wear due to low viscosity WILL NEVER be mitigated by the thinner oil since you never achieve an optimal viscosity range at mid-life of the oil.

Call me biased, but this is why Mercedes specs a 5w40 and uses a 20,000 mile interval vs the VW range of 5w30 and 30,000 miles.

Of course if you live in the US, VWOA wants a 5w30 run for 10,000 miles...Lord knows they want that car off the road in 150K so you come back and buy a new one.

Look at the PD engines and the cam issues. How many of those cars were running 5K oil changes on an approved VW505.01 or 507.00 oil and still managed to wear out the cam and lifters in 120K? Look at the ones running a 5w40 from day one (Turbo Diesel Truck non 505.01) and how many of those are in the upper 200K range WITH THE ORIGINAL CAM AND LIFTERS and I might add running 15-20+ mile oil changes!

 

I don't know what all that drivel is that you posted, but I couldn't follow it and there is no source listed, so...caveat emptor.

You should change your oil when it is nearly worn out. That point can be determined by lab analysis (such as submitting a sample to Blackstone Labs for testing). So change your oil at the mfg's suggested interval. Submit a sample for testing. Increase subsequent interval lengths until lab testing reveals you are near your oil's lubrication limit.

Its pretty simple. No conspiracy theories or "I worked in blah blah blah and the automakers are trying to screw you" nonsense needed.

 

I had a '04 Golf TDI, bought new. Oil change interval was 16,000 kms (10,000 miles).

Rarely made it to an oil change though. Tore the F-ing oil pan out on a regular basis.

And keep an eye on the turbo waste gate actuator. Horrible design allows dirt build up to tear the seal out of the shaft, thereby allowing water into the actuator. Doesn't cause a problem until the weather drops below freezing.

 

Ok cool thanks man! Any easy way to check that? I know the turbo is stuffed behind the motor

 

It's hard to get at. Best way is from under the car, but the shaft runs up from the actuator so you can't really see it from there.
I don't know if you should clean it regularly or not. I just know that I had to replace the turbo actuator with 120k on the car, and the local VW specialist (not the dealer) said that it was a fairly common problem.

BTW, you can't buy just the actuator, or at least you couldn't then. I found one off a blown turbo.

 

Of course lol nothing on those cars are easy and or cheap