[Porschedude]

Fred,

When you change the oil, try a different brand than you have been using. I experienced this problem with my 2.4L '72 911T. It would start smoking about the time the oil needed changing. I found that some oils worked better than others. I found that heavier weight oils, say 20-50w, worked a little better than straight 30w. I tired straight 40w one time without any problems; just don’t try this in the colder climates. Over the 14 years I owned and serviced the 911T, I must have changed or rotated the brands once per year. It may seem strange, but it helped my smoking problem. This only masked to problem with the engine, which was worn-out cylinders with a whole lot of taper. When I assembled the engine, the taper was right on the edge of the maximum. I drove the car for 12 years / 120k miles with little embarrassment from the smoking.

I started using 15-50w Shell Rotella in my 964 with 114k miles, and no smoking.