First, what model year Audi or VW TDI do you have? This page is for pumpe duse (PD) engines up to model year 2008. See 1000q: pre pumpe duse engine oil if you have a 2003 or earlier TDI sold in North America.
North American VW TDI, model years 2004-2005 for the VW Passat TDI, V10 VW Touareg TDI and 2004-2006 Jetta/Golf/New Beetle TDI are pumpe duse and require pumpe duse specification oil. If you can't figure out if your car is PD, use a PD engine oil because higher spec. oils are compatible with engines calling for a lower spec. but lower spec is not compatible with engines that require higher spec. oil. If you need help more identifying your car, take a look at 1000 answered questions: mk4 cosmetic differences to see cosmetic differences of the mk4 cars. Also see 1000 answered questions: direct injection vs pumpe duse to see mechanical differences that pumpe duse cars had and for an explanation of common rail vs. pumpe duse vs. direct injection.
NOTE - The VW Touareg TDI V10 got a DPF filter in 2006. (This exception also applies if you have a non North American car with the optional DPF). Because of the DPF filter, use the newer 507 oil. See 1000q: DPF regeneration and Adblue fluid FAQ for more details. All other 2009+ TDI should use the newer 507 engine oil.
Why should you go to the trouble of making sure the diesel engine gets the correct engine oil? Turbo engines require clean oil to lubricate their many moving parts under high temperature. Diesel engine oil has to sustain more soot than gasoline engines. Since your TDI has both, it is especially important to use the correct engine oil. Not using the correct oil could result in a refusal of warranty claim on the engine. Pumpe duse engine oils will also work on earlier pre pumpe duse engines but not vice versa. If you have an earlier pre pumpe duse car, using newer pumpe duse oil is not better. Linked here is a TSB regarding pumpe duse engine oil: engine oil TSB These oils are generally more expensive but are the VW spec oil for your pumpe duse engines.
I did not write best oil because what engine oil is best is debatable. Some pumpe duse engines have had excess camshaft wear even when using the correct VW engine oil. See 1000q: camshaft inspection and replacement to check for wear or replace worn lobes or bearings. Suspected causes are: incorrect engine oil (even when serviced at the VW dealership), dirty engine oil, soft camshaft lobes (defective construction), narrow lobes vs. older engines (bad design), high pressures on the camshaft lobes (needed in pumpe duse engines), unknown causes, or a combination of all or some of these - see the above camshaft inspection article for more details.
In any case, the only engine oil which will qualify for engine warranty coverage is the oil that is approved by VW. Some camshafts have experienced excess wear even with pumpe duse engine oil. Ultimately it's up to you to determine what brand/weight/spec engine oil you want to use. Some have suggested zinc additives like ZDDP to cushion the camshaft lobes but excess zinc can damage catalytic converters.
Pumpe duse engine oil must meet VW oil standards: 505.01, 506.01, or 507.00. Here is another TSB which lists engine oils approved by VW - right click, save as
or click to view. Scroll down to see the 501.01, 506.01, or 507.00 oils.
The recommended oil change interval is before every 10,000 miles. Trucking companies and other industrial engines sometimes use engine oil for 15,000-30,000 miles but they use oil analysis to determine when an oil change is needed because it's more economical for them. Passenger cars operate on different duty cycles and it's not economical to do regular oil analysis on your car so it's best to just change it every 10,000 miles. Changing your oil every 3,000 miles does nothing but waste of money and oil and modern gasoline cars also have recommended oil changes of 5-10,000 miles depending on use and oil type. Although synthetic is more expensive, the longer change interval cuts the number of oil changes in half, realizing a cost savings.
It is normal for the oil to be black, even when new. This is normal for a VW TDI and perfectly fine. There is a little bit of oil remaining in the engine when you do an oil change and it's enough to turn all of the oil black. To see how to do an oil change, refer to the how to lists linked in the blue button at the top.
Here are the links to the oil manufacturers' product information sheets, make sure that you check the specs for yourself! 1000q: engine oil reference list
Some approved oils are:
(full list in this .pdf file, right click save as. approved oil tsb)Castrol 5w40 TXT "german oil" synthetic meets VW 505.01 Note: This is NOT syntec 5w40, nowhere on the bottle should it say syntec. VW part# G052167A2 Note: this oil has been superceded with Castrol SLX professional OE 5w30.
ELF SOLARIS LSX 5W30 OEM approval for VW 507 (and VW 504)
ELF EVOLUTION CRV synthetic 0W-30 OEM approval VW 506.01 (and VW 506.00 VW 503.00)
ELF EXCELLIUM DID synthetic 5W-40 synthetic OEM approval VW 505.01 (and VW 505.00 VW 500.00)
Motul Specific 5w-40 OEM approval VW 505.01 505.00 500.00 and FORD WSS M2C 917A
Motul 6100 OEM approval VW 505.01
Anything else that is certified by VW as 505.01, 506.01, or 507.00.
Other places where you can buy engine oil that meets the VW TDI pumpe duse engine spec: (click links to compare current prices)
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