I have no problem with a first change at 5k, given the high amount of wear metals being thrown off during break-in.
But, 5k oil changes with 507 oil will almost certainly cause more wear to your engine over the long haul than will 10k changes.
Sounds crazy, right? But once you understand how these oils work, it makes sense.
When you do your oil change, the fresh oil is in clean phase, loosening and suspending deposits from the previous OCI. After about 500 to 1k miles, the clean phase is over and the lubricating qualities of the oil actually improve, and allow the oil to now minimize wear for quite a long time, until you change the oil and go through another cleaning phase (with the resulting poorer lubrication that comes with the cleaning phase).
So you can see that with a 5k OCI, you will put your engine through twice as many cleaning phases, with their attendant higher wear rates.
I doubt this would matter if done once or infrequently, but done every 5k for 30 or 40 OCI??
Put it this way...at the very least, you are spending twice as much money on oil and getting no benefit, and likely increasing wear a little.
Not a good bargain in my book.
A more detailed explanation is shown below, cut and pasted from TDIClub in a post by member Drivbiwire:
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The ORIGINAL factory APPROVED oil change interval is 30,000 miles! YES 30,000 MILES!!
Did you comprehend that?
THE ORGINAL OIL CHANGE INTERVAL APPROVAL IS 30,000 MILES!!!
Now that I have that off my chest,
VW reduced the interval from 30,000 miles to 10,000 miles in the US market...any guesses why?
Because people like you either:
1) Can't read the owners manual
2) Don't trust the car makers
3) Can't follow directions
4) Fail to adhere to the service indicator in the car
VW does NOT want oil change intervals of less than 10,000 miles due to how the oils function in the engine, shorter intervals INCREASE WEAR, Don't argue with me about it, if you take the time to track wear rates during an oil change at 250 mile intervals you can plot the reduction and stabilization of the wear rates out beyond 25,000 miles!
Think of oil as having 2 types of wear reducing additives, the first provides protection by/thru detergancy (cleansing of internal surfaces), dispersing soot, neutralizing acids (not an issue now with ULSD), and several other types as well. These additives are generally very specific to diesel engines and must pass specific tests in VW Diesel engines.
The next type of additive is a wear additive. These protect the engine where the thickness of oil may be too thin to prevent metal to metal contact. Other additves in this type range also provide protection to the cam and lifters, engine bearings, piston wrist pins etc.
Now pay attention, the 2nd group of additives account for less than 3% of the total volume of the oil. These additives also account for 90% of the engines oil protection! These additives require heat and pressure to bond with the critical wear surfaces, but due to the low percentage of additive in the oil they require time to fully place on those surfaces by the pressures of the component they are protecting. Example, an engine at operating temperature at the point where the cam presses on the lifter generates in excess of 90,000 psi, that pressure and the heat of the engine causes the 3% portion of the 1 micron thick oil film to form a crust or sacrifical layer at the point of contact. Since only 3% of the oil contains the wear additives, it requires hundreds of thousands of passes to generate a sufficient film to stop the wear at this specific point in the engine.
Everybody is quick to make the arguement that the old oil had these additives so they are already in place, right? not quite!
Remember the first type of additive? In that 1st group you had "detergents" that cleanse the inside of the motor. These cleansers are used up very rapidly after an oil change since they attack the remaining oil that was left after the oil change. These cleansers if you will also reduce the effectiveness of the high pressure wear additives...See where this is going?
Before explaining further, after that initial period the dispersants in the oil work to prevent the adhering of the particles in the oil to any of the internal surfaces. These additives are often unique to diesel engines are also the reason why the oil looks so black so quickly, they are doing their job by preventing the soot from building up in any one place instead they are dispersed in the oil evenly throughout the oil sump which prevents sludging and other contamination related issues.
Back to the detergents and the high pressure additives, the layers of high pressure additives leftover are not being replenished after the oil change due to the cleaning process that is going on with the new oil to neutralize the remaining acids, and other contaminants in the engine. As the cleaners in the oil are used up in the first 500-1000 miles, the wear additives are able to re-generate a protective layer in the engine that stops the wear at that location.
You break down the oils life cycle like this:
Phase 1: Detergants attack the internals removing accumlated contaminants, neutralize acids and force those into suspenstion in the oil. This period of time lasts between 500-1000 miles
Phase 2: During the first 1000 miles the oils viscosity provides the majority of the wear protection by virtue of the film it creates on the surfaces. This phase generates relatively high wear rates but due to the short duration this is accepted due to the removal of contaminants that could result in long term damage to the motor. Wear rates in the period of time are generally speaking 5-10ppm per 1000 miles.
Phase 3: Detergents are now used up and the oil additives are forming their protective layers in the "extreme pressure" regions of the motor. Now the oil additives are working in conjunction with the oil film and the wear rates drop from 10ppm per 1000 miles to around 1-2ppm per 1000 miles.
Phase 4: Longterm peace! The oil is operating in a period of equilibrium, the wear additives are placed, Oil viscosity is in perfect range for the engine, Dispersants are continually working to prevent soot and other contaminants from accumulating on the surfaces and wear rates remain between 1-3ppm per 1000 miles.
Phase 5: Oil run out, the oil during this phase begins to increase in viscosity (or thin in some cases), Extreme pressure additives begin to lose effectiveness due to increased concentrations of wear particles (VW tests out to 8%, most oil changes never see in excess of 2% after 30,000 miles). This is when you begin to see a rise in the wear metal formation in the engine. Often wear metals during this phase rise to the 3-8ppm per 1000 mile range. Notice that the wear metals being generated are still LOWER than they were in the first 1000 miles?
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Tim
It took about 5 minutes.
