the flyin' scotsman

changed the engine oil and filter yesterday with the speedo showing just below 233k kms and 15k kms since last change.

everything thing looked perfect so new Mann filter installed, new drain plug washer and ~approx. 9L of fresh oil. I use Rotella T6 0W40 for the winter and 5W40 in summer.

The engine uses zero oil in between changes and runs smooth........works for me so thought Id share...........YMMV

Petza914

Keep it up 👍

Matt O.

Wisconsin Joe

Why?

Honest question, not being snarky.

I drive truck, and they don't shorten the interval, even when the trucks get upwards of 600k miles.

jeff spahn

Exactly. We go 20,000 miles between oil changes on my Freightliner and Sterling trucks with perfect oil every time. (we don't put many miles on per year so that's why the intervals are so short)

Matt O.

Um, a Freightliner is not a Cayenne.

Recommend the OP simply do an oil analysis. When I took Mobil 1 to 9,000 miles vs 7,000 miles, there was a substantial difference in the result. OP might have different results with Rotella.

Petza914

Yup, same experience here on the UOA for both my 997s. Anything beyond 5,000 miles, the oil becomes more acidic (TAN still higher than TBN), the viscosity gets lower, as does the flashpoint, and most importantly, the Zinc and Phosphorous levels that protect the valve train start dropping below 1,000 ppm. Based on the 20 or so UOAs I've run, I won't run any oil, even synthetics, beyond a 5,000 mile change interval. On my supercharged RUF car, I run 4,000 mile intervals because the #s in the UOA degrade quicker after 4,000 than they do on my wife's regular 997 C2S, which remain fine up to 5,000 miles. All my vehicles that require 5W/40 weight oil get JGR Driven DT40 which has higher Zinc & Phosphorous levels and can maintain protection even up to 300 F. If I worried about using a Porsche A40 Approved oil, I'd use Motul xcess 8100 before the M1. For my older Porsches that need a thicker oil (modded 914 & supercharged 928), I use DT50 (15W/50).

Laura

269,000 miles on Turbo S, oil service with Mobil 1 every 5,000 miles. And she runs great!

Matt O.

That's a heck-ava lot of miles. Well done. How many have you put on her?

the flyin' scotsman

thats tremendous; I take it the engine is original?

Thats 430k kms, Ive a long way to go, yipee

Rod Croskery

T6 goes into my Ranger UTV and little diesel tractors. They start very well in winter with the new synthetic.

Dilberto

Mobil 1 always returned terrible UOAs.... even after 3500 miles. It shears down badly and the film strength of the Group III hydrocracked oil is nearly that of water. I've literally tried them ALL: Shell/Total/Castrol/Schaeffer/Liqui Moly/Pentosin/Pennzoil Ultra/Amsoil/Royal Purple etc... and my go-to oil is now Motul 8100 x-cess 5w-40, with top ups of Motul 300V Ester Core 5w-40.

Petza914

Dilberto,

Of those you listed, I agree with you that the Motul is the best, however the JGR DT40 is even better if you're not concerned about A40 approval. Phosphorous and Zinc levels remain higher at the same change interval, as does the viscosity, and it remains less acidic. Based on these last couple reports, I've now moved back up to a 5,000 mile interval on this 997 C2S. Mine, which is supercharged, remains at a 4,000 mile interval as it shows similar wear at 4,000 miles as my wife's DD does at 5,000 miles, probably because it's driven a good bit harder.

vandal968

Dilberto, why do you top-up with a different oil?

cheers,
c

Dilberto

Yeah, I even tried Joe Gibbs Racing Driven 5w-40 and Brad Penn. Good stuff for hard driving/racing,, nonetheless.