switched from castrol dino to mobil one.

bigchillcar · bigchillcar's Garage

i've always run dino castrol 10w-40 in winter, 20w-50 in summer, but a local porsche wrench who does some work now and then i'm not comfortable with on the new C4 convinced me to try mobil 1 in 15w-50, particularly since this engine (165k, well documented) is bone dry. damn the stuff is expensive! but one year or 15,000 miles between changes it says. we'll see how it goes.

anybody ought there switched from dino to synthetic recently? thoughts on the change? i've never run synthetic in anything i've ever owned.

RoninLB · 04-23-2007, 12:04 AM

upper piston side and ring is vulnerable to heat damage to oil causing coking. M1 15w-50 has the highest temp rating before Redline. M1 15w-50 is about 425F and Redline is about 450F.

forget about 15,000 mile change

I change oil right after winter cold ends and in Nov.

bigchillcar · bigchillcar's Garage

ron..so this is a good thing..?

RoninLB · 04-23-2007, 12:27 AM

Quote:

Originally posted by bigchillcar
ron..so this is a good thing..?

yep

M1 isn't the only synthetic you can use. I think the right formula Kendall is also very good.

Walmart sometimes has sales on M1 gallons. If you see a sale move quick.

dino oil can't deal with the heat generated at the top of the cylinder. Bruce Anderson has written about the issue.

livi · 04-23-2007, 02:46 AM

I have used M1 0w40 in my 85. Very happy with it.

Although, in the May issue of 911 & Porsche World, they claim synthetic oil is not suited for older 911´s. Period.

The never ending story...

GeorgeM · GeorgeM's Garage

I made the switch from Castrol 20W50 to M1 15W50 at 122K. At 137K it still runs like a top with no leaks.

I tried 0W40 a couple of years ago and it made my car smoke like crazy. Put 15W50 back in and it was happy again...

azasadny · azasadny's Garage

I just switched from Castrol 20W50 to AMSOIL 20W50 and my engine temps have dropped 10 degrees. I have the same small amount of oil weeping from the center seam of the engine case and it hasn't increased after switching to synthetic oil. The car seems happy and so am I...

Rot 911 · 04-23-2007, 06:04 AM

On the other hand when I tore down my 3.2 engine (worn valve guides) that had run on nothing but dino oil for 131,000 miles you could still see the hone marks in the cylinders, the internals were spotless and all within spec. Not saying synthetic is bad, just another viewpoint.

bigchillcar · bigchillcar's Garage

whan i was at wal mart last night and saw their prices on M1 gallons, i felt like i'd had my pocket picked at advance auto parts! i traded in a case of my castrol (returned it) and the diff i still had to pay for a case of the M1 was HIGHER than had i just bought the m1 at wal mart! wow.

wow, art..10 degrees?? that's quite an improvement! another friend uses castrol syntec and swears by it. i think it may actually be higher then M1.

bigchillcar · bigchillcar's Garage

whan i was at wal mart last night and saw their prices on M1 gallons, i felt like i'd had my pocket picked at advance auto parts! i traded in a case of my castrol (returned it) and the diff i still had to pay for a case of the M1 was HIGHER than had i just bought the m1 at wal mart! wow.

wow, art..10 degrees?? that's quite an improvement! another friend uses castrol syntec and swears by it. i think it may actually be higher then M1.

nesslar · 04-23-2007, 09:34 AM

Quote: "dino oil can't deal with the heat generated at the top of the cylinder. Bruce Anderson has written about the issue."
Admittedly I've not read Mr. Anderson's prose, but I'm just wondering, the high temps you refer to are in what kind of situation? Racing? Az. in the heat of summer?
Here in western Wash., normal driving (

) wouldn't good dino juice be just fine?
Seems to me that just maybe some people worry too much about these things, at least under normal, average conditions. No?

bigchillcar · bigchillcar's Garage

whan i was at wal mart last night and saw their prices on M1 gallons, i felt like i'd had my pocket picked at advance auto parts! i traded in a case of my castrol (returned it) and the diff i still had to pay for a case of the M1 was HIGHER than had i just bought the m1 at wal mart! wow.

wow, art..10 degrees?? that's quite an improvement! another friend uses castrol syntec and swears by it. i think it may actually be higher then M1.

bigchillcar · bigchillcar's Garage

looks like i'm experiencing some dementia...oops. lol.

azasadny · azasadny's Garage

I was surprised myself to see the 10 degree drop in temp after changing to AMSOIL 20W50, but nothing else has changed. Same engine, Webers, and fuel (93 octane premium, unleaded). I haven't notice any additional oil leaks, I still have the same minor oil weeping from the case seam. The car is running great, so i'll stay with the AMSOIL for awhile!

RoninLB · 04-23-2007, 12:54 PM

LubeMaster77 has great oil info in search. He's the real oil pro around here imo.

and others have reported good things on Amsoil.

sig_a · 04-23-2007, 01:11 PM

I switched from Castrol mineral oil 20w50 to Rotella mineral oil 15w40 new CJ-4 Triple Protection Formula with boron.

GothingNC · 04-23-2007, 01:27 PM

Quote:

Originally posted by sig_a
I switched from Castrol mineral oil 20w50 to Rotella mineral oil 15w40 new CJ-4 Triple Protection Formula with boron.

Same here

RoninLB · 04-23-2007, 08:53 PM

Quote:

Originally posted by nesslar
Seems to me that just maybe some people worry too much about these things, at least under normal, average conditions. No?

i'll look for Anderson's article later.

and in a way your correct about "average conditions".

RoninLB · 04-24-2007, 10:06 AM

found something Anderson wrote, although it's not enough info.

"My reason for focusing on the top ring land groove is that it is often overlooked or not given proper importance when checking a set of pistons and cylinders. Because the 911 engine is air-cooled, the top ring sees more severe operating conditions than a similar ring in a water-cooled engine..."

T77911S · 04-24-2007, 06:23 PM

for a non turbo, M1 or castrol synth. turbo i would go with AMSOIL due to even higher temps. the only reason i say M1 or castrol is that you dont have to order it. i am going to open a can of worms with this one, but i have read that changing your too often is bad. i can hear the keys clicking as you type in anger, or maybe joy at the thoughts of correcting me. so let me have it, but first read these 2 sites..........i must have head examened.

http://www.carbibles.com/engineoil_bible.html

http://neptune.spacebears.com/cars/stories/oil-life.html