[Biturbos4] Switching from dino to synth - lifter prob?

Keman keman at interwolf.net
Thu Jan 15 23:25:41 EST 2004


Don't use synthetic because it'll cause lifter problems? I strongly
disagree. Your owners manual strongly disagrees .. as it recommends 0W-30
which isn't available in a dino base.

Your S4 came with synthetic from the factory .. and in europe Audi actually
pays for it to be put in at every service. AoA has cheaped out ... but with
the new V8 S4 they may be forced to pay for it to be put in since it is
required for the new 4.2. I've been hoping that will be extended to the
biturbos as well.

I've run synthetic in mine since day one. Every tech at the shop does the
same. My rings seated at around 9000 miles and to this day my engine burns
no oil since, and it just ticked off at 79k miles. When I had the valve
cover off not long ago it was prestine, squeeky clean. My lifters are nice
and quiet. I cannot say the same for engines that run standard oil with
regards to cleanliness inside. Lifter failures on Audi's due to lubrication
issues are unheard of no matter what oil you run, and when people run their
engines with little or no oil (!!!) it's the camshaft bearings in the rear
of the engine that are usually wiped out along with the chain tensioner
pucks getting worn right through the nylon.

Some fear leaks if you switch to synthetic ... and I believe that this
concern is because synthetic is good at removing deposits. If said deposits
are what is preventing a gasket from leaking... then switching to synthetic
may "cause leaks" as the deposits are eroded away. Truely though, I think
this issue is better reserved for an old Chevy 350 with cork gaskets under
stamped steel valve covers than with the multi-layer composite stuff we run.

For another source of good information on turbochargers and synthetic oil..
check out "Maximum Boost" by Corky Bell. That reference is highly regarded
and Corky discusses the benefits of synthetic oil with turbocharging.

Was there a specific grade, ie: 5W-30, 15W-50.. that you inquired about?

Y'all will think I'm nuts, but I run 15W-50 M1 in the summer. I know, KKK
K03 turbos have small oil passages, and Audi says to run 0W-30. But Audi
didn't used to say that. In fact, they used to say before 1999 that you
should run 20W-50, and that you couldn't run 5W-30 when it was hot out, and
that if you did you must "avoid extended periods of hard use". The turbo
bearing journal sizes have not changed since then, nor have the
specifications of camshaft and crank clearances gone any tighter. I know
this because I looked them all up. The EPA mandates for fuel mileage
increased then though. Coicidence? I don't think so.

I ran 0W-30 for the first.. 55k miles of engine life. And that included a
bunch of track abuse. I kinda regret that presently .. (wish I ran thicker
oil while on the track) but things seem to be alright thus far.

So...  you've now got an audi tech saying he runs 15W-50, a dealership
saying not to run synthetic at all, the rest of the world and audi saying to
use 0W-30 which only comes in synthetic.....

It's your car. :)

- Keman

>> As they were dumping oil from my boost tubes, I asked if they could
>> tell if it was dino or synth oil (since I had just switched to synth
>> a thousand miles ago).  Both the service advisor and the mechanic
>> said to switch back to dino immediately.  They were quite clear that
>> I *would* have lifter problems (their words: "every time").
>>
>> Does any one have any information about this??



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