[Dadofour]

A buddy of mine has a 2003 996 that he bought recently with approx 15,000 miles on the clock.

He is adding a quart of Synthetic oil every 1000-1200 miles, with the exception of the second to last fillup when he used a different Synthetic than the standard dealer recommended Mobil 1.

On the last top up of the oil he discovered a chocolate (moca) brown sludge like substance inside the oil filler cap and inside the filler tube.

We understand that Porsche says that a quart every 600 is the cutoff for concern.

Questions:

Do you think the consumption rate is excessive?

and

Have you ever heard of this Sludge issue before?

He cleaned the cap and the filler tube.

His dealer feels it may be an incompatability issue between the different synthetic brands and weights.

Thanks

Than