While many folk speculate or are convinced that Mann or Mahle filters are
the only way to go, I have always had doubts that any filter is all that
much better than another. The one thing that has not been presented here
was actual facts on a filters ability to remove dirt. As some of you are
aware I have become familiar and am now a true believer on regular oil
analysis. This is a requirement for warranty for the Cat engine and
Allison transmission in my motor home to allow extended drains.

Back In March 2004, I obtained a 1988 Fox from the original owner. It had
only 14,470 mile on it. I changed all the fluids, using synthetic oil. The
tranny got Mobil 1, SHC 75w-90 and the engine got Mobil 1, 0w-40 and a
Fram TG2870A filter.

6,000 miles later I took an oil sample and sent it out for test. Results
for wear metal were as follows. Copper was 20, Iron 20, Lead 8, Silica
(dirt) 19. oil condition rated "A".

At 13,500 miles on the oil, the numbers were slightly higher , 36, 66, 35,
21 with a recommendation to change the oil and filter due to wear
particles. Condition "B". This took me by surprise as I usually get a
suggestion to change oil based on oxidation, nitration, or in the case of
the Diesel engine soot loading.

So I changed the oil and filter, again using the Mobil1 0w-40 and Fram TG
filter. I also replaced the air filter.

~11,000 miles (one year later) I did the oil testing again and got similar
results. Condition "B". So I changed the oil and filter except this time I
used the Mahle OC47.

My wife has been using the car a lot so we quickly did 11,000 miles and I
did the testing again. The results were alarming. Condition "C".

Copper was up at 78, Iron at 115, Lead at 100, and Si at 53.  This with
only 53,000 miles on the engine.

I changed the air filter and also the oil and filter. I am now trying the
Mobil 1 filter.

We'll see what happens.

Dennis