Re: Audi Factory Replacement Filters

[zm@mhcnet.att.com (Zafer Mehmood [209])]

>  
> What is the significance of the "turbo" marking on a filter cartridge, seeing 
> as the physical dimensions are the same?
> 
> Time for a chat with Tim at The Parts Department.
> 

I had a similar chat with Stephan at my local Audi dealer parts department.
His answer was that the turbo filter has "different valving" than the
regular filter, refering to the anti-drain-back valve I guess. My motivation
for the question was that the non-turbo filter is almost half the price
of the turbo filter. Anyway, since then I have been buying the turbo
filter from PAP at almost wholesale prices, so I'm satisfied.

There was some discussion earlier about filters with the anti-drain-back
valve and hydraulic lifter noise. The Audi turbo filter definitely has this
valve whereas the Fram doesn't. You can tell if the filter has this valve
if you try to pour oil thru the large center threaded hole. The valve
prevents the oil from going in. Found out because I'm in the habit of
filling the new filter with oil before installing it (builds up oil
pressure quicker on initial start-up). Also, when you remove an old
filter with the valve, a whole bunch of oil drains out from the passage
ways above the filter, since the valve had prevented the oil from
draining into the sump through the filter.

I use  Mobil 1 synthetic oil and the Audi/Mahle/Knecht turbo filter
on my '87 5000TQ with 130K miles and have almost no lifter noise (may be
5 seconds of noise if the car was not driven for a couple of days).

-Zafer