Date: Sun, 17 Oct 1999 12:02:51 -0700
Reply-To: "T.P. Stephens" <doktortim@ROCKISLAND.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "T.P. Stephens" <doktortim@ROCKISLAND.COM>
Subject: Re: Oil Filters
Content-Type: text/plain; charset="us-ascii"
At 11:32 AM 10/17/99 -0600, you wrote:
>Hi all
>I have been using the cheap oil filters from
>Canadian Tire for years with no apparent bad
>effects. After joining this List this summer I
>have become sort of paranoid and confused as to
>what should and should nod be used in a Vanagon.
>
>Anyway, I am about to change the oil again for the
>winter, using 5W30. I live in Edmonton, Canada.
>I have bought a Bosh 72150 filter (it has a spring
>like thing in the middle) and a Canadian Tire
>filter (hollow in the middle, no spring).
>Which is better, and why?
Empirative evidence says they are different.
Question is, WHY are they different. Several
possabilities exist. Both meet specifications,
one does and one doesn't, or neither does.
The vehicle was originally equiped with a filter made by Mahle.
We KNOW that one meets specification because it was manufactured
by Mahle to VW specifications and tested by VW to insure it meets
the requirements of a specific motor design with regard to
quality of materials, flow rate and volume, particle size capture,
contaminant load capacity and whether or not a backflow valve is
incorporated to prevent momentary pressure loss upon startup and/or
a pressure relief valve in case das dumkopfen believes in add a
quart only as needed and never change the oil unto failure and/or
a pressure maintenance valve to reduce pump pressure to a predefined
constant and/or other features with which I am unfamiliar.
What is the problem with the Mahle/VW filter??? Because of the unique
specifications that must be met for this design it cost more to make
than a filter without these qualities. Dang things list over $9.00 US
in the Mahle label. Probably similarly priced in VW logo at the dealer.
Up through the early 90's European vehicles I am familar with and stock
filters for, most if not all come with Mahle, Knect, Hengst or Mann
filters all of which I carry all the time. Bosch is the only aftermarket
German filter I am aware of commonly available in America. I also carry
all the time Bosch filters made in Germany. I do not carry Bosch filters
made in Spain.
Since they are all of the DM school and supply massive numbers
of other components as original equipment to VW, I would expect it
would meet VW specifications, however, unless VW says it is approved
for use because they TESTED it, you will have to test it to PROVE it
meets specifications. Of course, you'll have to convince VW to give
you the specifications so you can compare what Bosch says are the
specifications and compare both with the empirative evidence you develop
from your TESTS, if you really want the TRUTH.
Since I don't have the resources to independantly determine the TRUTH,
the only thing I know of a certainty meets specifications is the Mahle.
I am certain to a 2 sigma probabilty that German Bosch either got the
specifications from VW or opened and inspected and tested the Mahle items
against their own design. It may even be possable that Bosch buys filters
from Mahle with their logo for the German Production and makes their
filters for Japanese cars in the new plant in Terra del Fuego. Just
something in the long list of things I don't know.
I dare you to find one seller of any filter brand that will not state that
it "meets original equipment manufacturer specifications". If you believe
they couldn't say it if it wasn't true, buy the low down cheapest filter
you can buy and ask for an extra discount if you buy them a dozen at a
time. If you never let the oil get past brown before you change it, your
experiment might be a success and then again it may not. When it hits
-30 farenheit in Edmondton, will the 5W oil flow enough cold through that
filter without busting the seam??? Let us know.
If you use the Mahle filter and keep the oil clean, you can easily forgo
changing the filter every time with no possabilty of a problem, so now
we have the effective price of filters cut in half to $4.50 each, and
that is for the only filter we know for SURE doesn't compromise the DM.
If certainty is security for you, you know what to do???
Can't find the Mahle filter right there handly at the local Mall???
I have no idea what if any duties might be involved, but if you want
to buy them 6 at a time from me, I would be happy to offer a not
immodest discount to the above prices.
>Can the spring in the Bosh filter get stuck,
>rendering the filter useless?
Only if abused by rediculous expectations.
Doktor Tim
Maintenance Repair and Restoration of European Vehicles
San Juan Island, WA