FlyingDog

There is a range for the 10 and a range for the 30. The "high mileage" oils are just higher in the range. I saw an article a few years ago where somebody sent a few oil samples for analysis (at Blackstone IIRC). The high mileage oils were all one viscosity range higher than published on the bottle. Maybe some oil companies add seal conditioners and maybe they do some good.

H2

I'm not a Mobil 1 fan for one reason....in one of my 928s one of the valve lifters makes a noise when idling on Mobil 1...but goes totally away with dino. I'm guessing that synthetic must be "too thin" to keep the valves pumped up. Change the oil often and I don't see why a modern dino oil wouldn't be as good as anything. Nope...I've not tried Amsoil...for the same reason I don't run Mobil 1.

Harvey

mark kibort

amzoil is a different animal to Mobil 1. (only in respect to what the oil pressure is when hot, which could be the reason for the lifters not pumping up)
i totally agree that some dyno oil, changed frequently, does do the job. Im starting to remember a test that reallly swayed me away from dyno oil

mobil 1 after 1000miles vs kendal 20/50 and then the qualities of amzoil and redline at 5,000miles. the kendal was equal to the others after 1000miles , but degraded quicker with age. mobil 1 was the worst of the bunch, especially after 1000miles. thats when i figured change the oil every 1000miles with kendal (during race use) and 3000 miles with amzoil or redline. cost equaled to be the same in the end

MK

mark kibort

or real life experiences.

what we need is a test of the oils at 280F!

mk

jon928se

I used to use first press virgin (ain't that a misnomer - can't be virgin if it is second press) Now I only use Extra Virgin - all those extra virgins to squeeze mmmmmmmmmmmmmm.

Can't we use Castrol R - I love the smell of that stuff.

Extra Virgin Castrol R - Heaven.

ew928

Castrol. Wasn't that fresh pressed Castor Oil?

Excuse me miss, are you a virgin?
Synthetic and nubile wimmin has totally different connotations. (They do test for siilcone in oil analysis from the one's I've seen)

Fabio421

I am appalled. The poll results have been faked and Jim M. has comitted voter fraud by voting twice. I demand a recount, and a choice for 0w-40.

H2

0-40 oil sucks in the 928...didn't anyone tell you? (just kidding).

H2

svp928

I've used Mobil-1 15-50 for 11 years, including a fair number of track days. Never had a problem...120k miles on the engine. No leaks, ticks, fleas or mosquitos.

IcemanG17

I heard that all the newer Porsches are designed for the lighter oils......like 5-40.....if you put a 20-50 weight into them it messes up the variable valve timing...since it is oil driven....& very sensitive to oil weight....my 06 Acura uses 5-20W....that stuff has gotta be like water!!

I previously used Mobil 1 15-50...& had no problems with it...but just switched to Amsoil Racing 20-50 (Amsoil does make a standard 20-50).....do I notice any difference.......not really......since I haven't got the engine hot enough yet to tell....but it does take longer for the oil to heat up and start dropping pressure at idle...but it does stay .5 to 1 bar higher at idle than the M1 did....typically the M1 would be 2-2.5 bar warm at idle vs 2.5-3 for the Amsoil....

ew928

How'd you keep the 5W-20 from leaking past the plastic bottle seam, Brian?

Guess all the fuel mileage concerns has manufacturers chasing the least engine internal resistance.

fraggle

I'm sure Porsche destructively tests an S4 engine or two on the latest oils every couple of years to stay up on giving us advice.

IcemanG17

Well I don't change the oil in the Acura...I have the dealer do it...so I dunno...but I just think that 4.5qts of 5-20W isn't very much in an engine that makes 260hp and spins to almost 7,000 rpms..... I don't know if it has a cooler?

underdog928

Just changed from dino to Mobil 1 - 20w-50 at 154,000 miles. It may be all over the driveway in the morning. Wish me luck!

Big Dave

Thanks for all the replies. I picked up some Rotella Synthetic 5w40 at Wallyworld. It's the first time I'm using synthetic in the 928. I intend on driving the 928 during the upcoming cold Michigan winter, so I'm not comfortable using a 15w or 20w viscosity.