PHIL928

I don't see why this is a relevant thing to test, oil pressure of less than 2 is merely showing that the oil is not the I'm pretty sure there's a reason why 3 bar is at the middle right?

antlee928

The oil pressure guage is not an exact measure of oil pressure but simply an indication of approximate pressure. From my experience and from all the 928 specialists I have spoken to (including David Heningway's Book on How to Buy a 928) the general rule is that cold engine should show at least 4 and preferably 5 bar via the gauge. A heat soaked/hot engine should show preferably at least 2 bar. Don't forget that the sender units can become lazy and also fail over tome. They can also get sludge or gunk clogging the pressure sensing pin-hole on the sender. Oil pressure is very important in these cars and if you are concerned then get your 928 specialist service shop to correctly check using an external gauge. When I had this done normal oil pressure at about 2000rpm should be around 8-9 bar.

When I purchased my S4 oil pressure as read via the cabin gauge was OK (within the range noted above) After I did my first scheduled oil change the pressure as measured by the cabin gauge was suddenly reading between just under 2 when hot and I was unable to get it above 4 bar under revs. I changed from what I believe was Mobil 1 51w50 to Penrite 10W50. So I quickly changed to a Penrite 15W60 a slight improvement but still not good. So I had my service shop check pressure to find that all was OK and it must be either gauge or sender unit. It turned out to be the sender unit.

My advice is if in doubt, have the oil pressure professionally checked and/or consider sender unit change (reasonably straight forward DIY).

Cheers

Hold On

I use M1 15-50W High zinc content, high thermal breakdown limit, blowby on "boost" doesnt lower my octane rating.

spanky

911s gets Mobil 1 V twin 20/50.
944 na gets Mobil 1 15/50.
951 turbo gets Mobil 1 V twin 20/50.
240 Z gets Mobil 1 V twin 20/50.
318 I gets Mobil 1 15/50.

PHIL928

I stand corrected, that contract belonged to Shell before Mobil 1.

"We are happy to say that Mobil 1 0W-40 is the factory and service fill choice for almost all Porsche vehicles since 1995." http://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/Motor_Oil_for_Supercharged_Porsche.aspx

alabbasi

In my 1997 Mercedes Benz E420 which is a 4 cam 32v v8. I've used Mobile1 15W50 for pretty much 8 years. On the last oil change, I switched to ENEOS 0W50 because I had some sitting on the shelf as I intended to use it on my old 79 Mercedes Benz 450SEL 6.9 which is dry sump and was not liking the 20W50 oil that was in there during the winter. I ended up selling the car before I changed the oil so I had 3 gallons sitting.

It's been in there for about 9000 miles and the car runs great with it. Noticeably quieter then before.

On my old cars, I had always used Castrol 20W50 until Walmart had a special where they were selling 2.5 gallon jugs of Shell Rotella for $13. I bought about 12 and have just run out.

I'll probably switch back to Castrol and use a zinc additive.