I must take some exception to the Brothers’ observation that the first caller’s husband is ruining his VW TDI by only changing the oil at 10K intervals. The manual calls for 10K intervals (with the normal caveats) but the manual also calls for a full synthetic. Being the proud owner of a 98 Jetta TDI and changing the oil and filter at the recommended intervals that I am not having any problems.
Sorry (I hit the enter key too fast) I am referring to the show that aired in my part of the country on Saturday January 26, 2008.
I would add that VW not only call for synthetic, but the specifications have gotten stricter on the newer models and VW has their own specifications for oil. Anyone owning a VW TDI and does not use a oil meeting those specifications is a fool.
Agree; Volkswagen is very fussy about oil, and you have to meet their spec. There is a general trend with European cars to longer drain intervals to cut down on waste oil. Having said that, if I owned a VW, I would probably change oil more often than the 10,000 miles interval, just to be sure.
How many miles do you have on your Jetta?
We have been using the same independent mechanic with good results for 30 years. According to him, the manufacturers that specify very long oil change intervals have overestimated the life expectancy of the oil. By the time these engines reach 100k miles, they show symptoms of the kind of oil break down that results from not changing it often enough.
Agree; that interval is only OK for cross country driving at legal speeds without a load. Such driving is rather unrealistic, unless you are a traveling salesman. I would cut it in half and use 5000 for normal daily driving.
It seems that whether they are talking about changing the oil or anything else, Tom and Ray seem to have a one size fits all answer for many questions. This leads to them often being wrong.
There has bee some interesting studies that indicate that new oil may not protect as well as somewhat older oil and that if you change too often you can actually get more wear. It should be noted that the difference is very small however.