Synthetic Oil - Diesel Engine - Proper Oil Change Interval

I have a new 2010 VW Jetta TDi (Diesel). The owner’s manual states that I only need to perform an oil change (using synthetic oil) once every 10K miles. The mechanic claims that I need to do it every 5K miles. Obviously the salesman was pitching me on it being a low maintenance car and the mechanic is trying to sell oil changes.



What is the proper interval?

I would follow VW’s recommendation, making absolutely sure the oil meets VW’s specs. Not all synthetics do. More often won’t hurt, of course. If you want to keep this car for 20 years and 300k miles (few do), then it might not be a bad idea.

Germans don’t keep their cars very long; they trade them long before serious wear occurs. Many leave the country for Africa and other developing regions.

Europeans are obsessed with reducing wast motor oil; all oil in Germany has to be recycled!

You, as an owner, are mostly concerned with having the engine live a long and happy life. That is best done by changing oil at about 5000 miles for normal mixed driving. I would only go 10,000 miles if all my driving was highway.

So the mechanic is basically correct; he does not have to toe the environmenntal and sales hype.

However, if you want to pass the car off on someone else after 3-4 years, the 10,000 mile interval won’t hurt you, just the next guy.

VERY IMPORTANT!! If you want your warranty to be honored, be SURE the oil you use meets VW specs for your car…Double-check this, as they will NOT honor the warranty unless you can PROVE you were using the “correct” oil. I would buy a quart bottle of the “correct” oil from the Dealers parts department window so you have a sample of it…

It is somewhere between 5k-10k all depending on your driving conditions. Your oil for the car has a special VW spec ???, make sure whatever is put in meets it.

Irregardless what you pick make sure to actually check the dipstick occasionally. It is NORMAL for even a brand new car to consume oil between 4k-10k miles.

As I recall that engine needs 507.0 (or newer when newer comes out). You need to use the oil recommended, even if you are going to change oil at every 2K. Use the right oil.

Back in grandpa’s day, no one would try to get 10,000 miles on an oil change. Those cars and oils just would not stand up to it. Modern oils and cars are far far different and better. Just follow the recommendations from VW, not a dealer not a quick oil change place etc. There are fewer oil related problems today and in grandpa’s day.

If you want to change the oil more often, go ahead. It will not hurt.

Remember those recommendations are for average conditions. If you drive under harsh conditions, then you should find a second recommendation for shorter change intervals in the owner’s manual. Follow those.

Look for specs on the oil that meet and/or exceed ie. VW 502.00, 505.00, 505.01 If a mechanic doesn’t know that an O.E.M. or dealer doesn’t have a case to void a warranty if the failure doesn’t originate with the oil needs to go to “Grease Monkey University”.

If you haven’t learned by now that a quart of special oil for your TDI costs $8 to $12 each, when you do, you might want to change oil at the 10K intervals. Changing oil at 5K miles will blow a pretty large hole through any thoughts that you might have about driving a VW TDI diesel for economy.

I suggest that you go to TDI club and look at their Fuels and Lubricants forum to benefit from the experience of fellow TDI owners. VWVortex.com also has an oil forum.

With diesels it comes down to the soot level and the ability of the oil to keep it small. The dispersants and detergents do that job. Otherwise, diesel service is much easier on oil than gasoline service. I’ve see TDI’s get 25k out of a single fill with a bypass filter installed.

10k, done in a timely manner, should be no issue for an approved oil.

The funky nature of the Teutonic engineering will kill that thing before the engine gives you trouble. The parts are obsolete 10 minutes after the thing hits the assembly line. Most 10+ year old Audi owners are paying through the nose when the sophisticated components fatigue. We do too, due to the continual free fall of assembly line patents vs. aftermarket patent sales, but the Germans leave a more “scorched earth” in their wake in terms of $$$.

Ask the mechanic if he’s going to pay for the change at 5K. Your free maintenance covers the change at 10K not at 5K. Further, a change at 10K intervals is more than adequate. I’ve got an 09 TDI Jetta with the same engine as your 2010. I had an oil sample analyzed by Blackstone Laboratories after 5K. The analysis indicated that the oil was good for many more miles. I had it changed after 10K miles. I had it analyzed again by the lab just before the 20K service. The oil at that time had almost half of the original additive package, and the metals in suspension were minimal, so it could have gone even further than 10K miles.

In summary, assuming you use the proper 507 VW specification oil, the oil is easily good for 10K miles. Just go by what your Owner’s Manual recommends. (10K changes)