M758

I agree. Here in Az it never get really cold so I run 20w50 year round. However in Iowa I would use 10-40 in winter, but not in the summer.

odurandina

"This is a very difficult topic to comprehend. Everybody including good mechanics think they are experts in this field but few understand engine oils. Most of what I hear is the opposite of the truth. It is however easy to see how people get mixed up as there is always some truth to the misconception.... The greatest confusion is because of the way motor oils are labeled. It is an old system and is confusing to many people. I know the person is confused when they say that a 0W-30 oil is too thin for their engine because the old manual says to use 10W-30. This is wrong." — JE Haas.


i've heard several of the smartest guys on the Porsche 4 cylinder forums saying 0w40 is way too thin. and by the same token, Mobil doesn't even offer a 10w40 anymore, except in a high-mileage formula... why ? too thick at startup. today's synthetic oil technology offers significantly, better options to help our soft engine bearings run as far as possible.

there is a great article on this subject at the following link;

http://www.bobistheoilguy.com/motor-oil-101/

http://www.bobistheoilguy.com/motor-oil-101/

http://www.bobistheoilguy.com/motor-oil-101/

http://www.bobistheoilguy.com/motor-oil-101/

http://www.bobistheoilguy.com/motor-oil-101/

http://www.bobistheoilguy.com/motor-oil-101/

http://www.bobistheoilguy.com/motor-oil-101/

http://www.bobistheoilguy.com/motor-oil-101/


at the bottom of the page you'll see a red patch that says "chapter." it would have been less confusing if it said, "please proceed to the following page, or lose out on learning the truth about engine oils." in any case, simply click that icon to continue.

odurandina

and if you somehow have a learning disability, and you have to struggle just to get through page 2,

if nothing more, learn and master the first graph shown there.


0w synthetics flow like regular oil does a few minutes after startup.

that is so say, it has the same thickness when the engine is ice cold as a 10w, or 15w oil has after the car has been running a while.... but it does this when ice cold--the moment when 90% of the damage we do to our engines occurs. if this concept is too radical for you all, then consult the automakers and their white papers. ask yourselves why a Ferrari F-430 has a maximum range between 0w30, 5w30 and 0w40 synthetic oil. why ? startup. the effin' engine is expensive to fix. so the solution is not to destroy it in the first place.

oh, our cars are different? yes, our cars require at least a 12 weight oil at 200 degrees. that would equate to 40 weight oil. show me a 944 that has failed running 0w40 or 5w50 oil. they fail because of damage done to the bearings during hundreds of cold startups. then finally being pushed under high performance after the bearings are already shot. but the posters say, "my oil failed today and i spun my number 2 rod bearing"... no d_ckwad, your bearings were destroyed before you even started the car... 40 and 50 weight oils run at something like a 12 and 17 weight respectively at operating temperature. the key is never getting to the point where the bearings have been damaged in the first place.

synthitic 5w50 is not a magical, multi-grade synthetic that will fall apart like it's conventional mineral counterpart... but the snake oil salesmen here will keep telling you all to run 15, 20w50 oils when it's freezing cold outside. the maximum thick oil we should ever be running in the winter would be Mobil 1 Racing 0w50 oil (the best oil on earth, period). or the less costly 0w40 or 5w50s.

but, wtf.... there's no cure for stupid.



turbocharger video

http://www.youtube.com/user/Official.../3/j-4WnBc3CKY




,

86 951 Driver

I will be running brad penn 10w-40. If it gets really cold here this year I will switch over to 5w-40 rotella oil.

VirginiaF1

Any Rennlister with 9,000+ posts gets my attention and this BobOil article series is a great example of why..

The axiom of " use the oil viscosity that gives you 10 PSI per 1,000 RPM ... based on your driving conditions." is so simple and easy to apply.

For me, Haas' assertion ( one I now trust ) that my VR1 20w-50 is "too thick at start-up" has me considering Castrol's newish 5w-50 Syntec... despite the 40% price diff.

When I called Castrol yesterday, they would ONLY release their ZDDP levels (1300ppm) on this 5w-50 as they are specifically (though of course not exclusively) marketing it to owners of " Flat Tappet Performance Engines"...

All other Castrol products consider their ZDDP levels to be " proprietary information not to be revealed ".

IIRC, several Blackstone reports showed a max 800-1000ppm for any unused Castrol product.

And I do recall DE racers finding that some Castrol oils failed to hold up ( carbonizing/flashpoints and TBN's post-race).

Reading this forum always teaches something I need to now.. Thanks all!

ernie9468

[QUOTE=VirginiaF1;8872504]Any Rennlister with 9,000+ posts gets my attention and this BobOil article series is a great example of why..

The axiom of " use the oil viscosity that gives you 10 PSI per 1,000 RPM ... based on your driving conditions." is so simple and easy to apply.

For me, Haas' assertion ( one I now trust ) that my VR1 20w-50 is "too thick at start-up" has me considering Castrol's newish 5w-50 Syntec... despite the 40% price diff.

LOL you do believe in Santa Clause do you?Do a search for all the oil tread started by our 9000 + post friend here then maybe the Sun will come up & shed some ligth on you.___Allan no offense meant but you know what I think & how I feel about all that oil bull.Hope it don't keep use being on the same side on some other subjects. In the mean time lets have a good!!!!

VirginiaF1

Santa Clause: No
Santa Claus: Yes

It sounds quite reasonable that the higher the CentiStokes number at start-up, the less flow is occuring until 190F is reached... ya?

And so, I'd like to find some wear tests on various cST numbers...

I've read on here and on Pelican that flow & film strength and not excess pressure is what protects our metals..

Just trying to learn...

odurandina

everything that Bob the Oil Guy, Mr. Haas, and myself have been talking about is the truth...

to demonstrate;

we needed at least a 40 to 50 weight oil (depending on the type of driving) running in our cars when the engines were new... but now with our aging bearings, it would indeed be better to be running 50 weight oil more and 40 weight oil less... especially if you drive your cars hard. but there is a significant problem.... the 50 weight oils aren't very good at startup (except Mobil 1's 5w50 Rally Oil and 0w50 Racing Oil). in fact they're rather bad, even in the summer.

but is this true or just a bunch of new age, oil bs ? it is indeed true, and i'll demonstrate....


let's say tomorrow morning will be 40°F.... at this temp my Mobil 1 15w50 oil will be way too thick at startup. with a weight somewhere near about 300 at that temperature.... in fact the stuff is actually so bad, that when my engine's moving parts reach a temperature of 104 degrees, my oil will still be too thick, and it will have a viscosity of exactly 125 weight at that moment. still way too thick to properly lubricate my engine.... when this oil reaches full operating temperature, it will, of course, be doing a lot better... but the damage will likely, already have been done.....


in a moment, i'll compare oils. and show you that for beginning with those cold fall mornings, it's already time to change to a better oil... since so many of you all loathe Mobil 1 products, i'll use another popular oil as a demonstration.... a slightly thicker oil from Redline...

at 104°F and at our engine's operating temperatures. the numbers don't lie..... doesn't matter if you consult with Amsoil, Mobil 1, or Redline, or whomever. it will all be the same. do your re-checking, and see if bob the oil guy says anything different than what you'll discover by doing the research....

ok, right from their webpage;

http://www.redlineoil.com/product.aspx?pid=6&pcid=21


viscosity grade Redline SAE 15W50

Vis @ 40°C (104°F): 138 ...... Vis @ 100°C (212°F): 19.6

the Redline is 138 weight oil at 104°F and 19.6 weight at 212°F (near operating temp)....



my Mobil 1 15w50 is similar at at 104°F having a viscosity of 125 weight

and 18.0 weight at 212°F (near operating temp)....

http://www.mobil.com/Pakistan-Englis...il1_5W-50.aspx


obviously, we like the 18.0 and 19.6 weights at running temp.

so, can we get nearer to these numbers at running temp, but have something that flows better at startup?


the short answer is yes.


.

Arominus

So umm what should i run to survive a start up @ -15f? ill have a few of those this winter. I was thinking the mobil 1 0w-40 after reading a bit on bobs site as apparently is one of the better oils mobil 1 makes. Right now i've got m1 10w-40 HM to get me through to the start of winter.

odurandina

here are some oils.... and how they compare to our 15w50 pillars of marble.


oil/SAE grade ............ visc @ 104 degrees Farenheit ............ visc @ running temp/212 F.

Redline 15w50 ....................... 138 ............................................... 19.6

Mobil 1 15w50 ....................... 125 ............................................... 18

Mobil 1 5w50 Rally Oil ............. 108 ............................................... 17.5

Mobil 1 0w50 Racing Oil ........... 100 ............................................... 17.2

Mobil 1 10w40 ........................ 96 ................................................. 14.7

Mobil 1 0w40 .......................... 75 ................................................. 13.5


the 0w40 isn't ideal (no oil is ideal). but the real question is can it help prevent our engines from being damaged during the winter at startup? the answer is clearly yes.... you also see from this graphic why the 0w50 Racing Oil is clearly Mobil 1's best product, as it offers the most protection under maximum performance conditions while still being able to flow reasonably well in the cold.... funny, it's the oil they recommend for a race car yet doesn't offer as much viscosity as their 15w50... but, yet it's what they recommend for racing engines. i'm must admit i'm incredulous... if we all agree that the 50 weight oil is what we need for our soft engine bearings, then, one of these high-flow-at-startup-oils is what we need to run in the winter. i know at least one of the 968 guys runs it; but at $17 a quart you gotta decide if that fits into your budget...

my solution would be running a mix of 0w40 and either 5w50 or 0w50.

the slightly higher cost for the 5w50 is worth it and you can order either hte rally or racing oils from their website.


there's a reason why the recent 0w20s, 30s and 40s are oem for all today's cars... the old way of running the 10w's, 15w's and 20w oils in the winter is not the right way. these oils are silent engine bearing killers, and the automobile manufacturers have thousands of reports proving it.

the 0w40 and all the above oils have plenty of zddp for most driving situations.

the Mobil 1 Racing oils have the maximum zddp @ 1,800 ppm.

333pg333

So when these false prophets masking themselves as actual in the field technicians/engineers/mechanics see Porsche motors with premature engine wear that were running on a Mobil synthetic product vs opening up motors that have only ever run on 20w/50 dino oils all their lives and look brand new inside...well obviously they're own eyes are lying to them and they in turn are lying to us. We can only ever believe Bob the oil guy who also champions the words of a so called expert with the initials D.H. who I believe might own a Boxter tiptronic but doesn't work in the industry and refuses to answer topical questions plus contradicts himself on various forums...hmmm, I wonder who I'll choose to believe...???

http://forums.pelicanparts.com/porsc...4-sm-oils.html

There's an oil thread....^^

VirginiaF1

Hi Patrick.. In trying to rectify both schools of thought:
- Were these 20w-50 motors perhaps mostly run during the warm summer months?

- In OZ, are the daily drivers ( like me in US) starting their motors for 6 months straight of the year in sub 75F/24C temperatures? Do you mostly see DD's or summer -only 944's?

- Were these clean 20w-50 motors always taken down to the bearing/journal levels for inspection?
Or had those bearings you've seen represent a small % of the total engines seen?

Thanks in advance!
Just trying to come up with a control factor for the possible variances.. to help me make a switch.
Cheers!

odurandina

i was going to say the same thing. of course i would run a 50 weight oil in australia. but if what he was saying were true, there would be no 0w oils. there would be no purpose for them whatsoever. but, quote all the idiot automotive and lubricant engineers including the Porsche people since they prescribe plenty of 0w oils for the newer cars.

if our manuals were written today they would specify one or a range of the follwing grades.

0w40, 5w40, 5w50 synthetic.


"90~95% of all engine wear occurs at startup."




our rod bearings are damaged in this way over many years of cold startups with 10w, 15w, and 20w oils.... long before they finally fail when pushed hard.

Jay Gratton

Alan Caldwell (PCA Tech Chair) strongly suggests NOT using anything less then 10W-40. I always used 20-50 in the summer and stored the car with 10-40 in the winter. i would probably leave the 10-40 in the car for a few weeks when I got it out as well and then changed it to 20-50.

Mobil 1 sucks, use Amsoil!

xschop

The 944 engine is just like my Yamaha motorcycle engine...Flat tappet... For years (around mid 90's) our group was all the sudden burning cams and main/rod bearings. It was discovered that the name brand engine oils stopped adding Zinc and Phosphorous. The EPA made them eliminate the two in the early 90's. The reason why is the Zn and Phos compounds readily bind to Palladium and Platinum, the main and expensive catalyst in the Cat converters. So it's a double edge sword as far as ZDDP is concerned. And Allan is right, most people don't realize that synth oils are a different ball-game that dyno oil. The main difference is that on a molecular level Synths are engineered to fold or coil up, increasing viscosity as temperature rises and vice-versa (like denatured protein). The ratio of the different molecules is how they formulate the various oil-weights. Also these molecules do not break down into acids readily like the long chain hydrocarbons of dyno and don't become acidic easily, the main reason why you can go 2-3 times further on oil changes.....