Otherwise why would industrial engines applications use them. I have an Franz system on my 97 Powerstroke and I change oil around 20K. I change the tp at 4k and the full flow at 5k. I use Delo 400 and send a sample to blackstone once a year. Been on the truck since she was a baby. 150k presently. Plan on 500k+ before retiring but coud go many more miles I am sure. It has save me approx 50% on lube charges over the years. This is not something you would want if you only keep the vehicle for a short period but if it is a keeper, I'd recommend it. JMHO
Bud

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1987 300D Turbo, 175k mi., 1998 BMW 323i Convertible, 1997 F250 4x4 7.3L PSD