Dharn55

Stopped using Mobil 1 0W-40 after the repair of my intermix. I now use Castrol Syntech, 5W-40 in the cold weather and 5W-50 in the hot weather. Based on the reformulation of Mobil 1 and I don't like 0W oils. I think many manufacturers have gone to 0W oils for mpg reasons as opposed to how good a lubricant and how good the protection of the oil is. Just my opinion. My Ford Expedition, F250, Taurus and my Chevy 3500 cargo van all list 0W-30 and I run 5W-40.

BruceP

Doug, maybe you can explain something for me, since you seem to know your stuff.

Isn't the '0' end of the viscosity rating just the cold viscosity? In which case, it seems to me that it's more protective than an oil with a heavier cold viscosity since it distributes through a cold engine more readily. That's how I got it in shop class, and that's how I always heard it during my years in the car biz. At operating temps, the '0' is irrelevant. What am I missing?

ivangene

google:

The Society of Automotive Engineers (SAE) has established a numerical code system for grading motor oils according to their viscosity characteristics. SAE viscosity gradings include the following, from low to high viscosity: 0, 5, 10, 15, 20, 25, 30, 40, 50 or 60. The numbers 0, 5, 10, 15 and 25 are suffixed with the letter W, designating their "winter" (not "weight") or cold-start viscosity, at lower temperature. The number 20 comes with or without a W, depending on whether it is being used to denote a cold or hot viscosity grade.


The temperature range the oil is exposed to in most vehicles can be wide, ranging from cold temperatures in the winter before the vehicle is started up to hot operating temperatures when the vehicle is fully warmed up in hot summer weather. A specific oil will have high viscosity when cold and a lower viscosity at the engine's operating temperature. The difference in viscosities for most single-grade oil is too large between the extremes of temperature. To bring the difference in viscosities closer together, special polymer additives called viscosity index improvers, or VIIs are added to the oil. These additives are used to make the oil a multi-grade motor oil, however it is possible to have a multi-grade oil without the use of VIIs. The idea is to cause the multi-grade oil to have the viscosity of the base grade when cold and the viscosity of the second grade when hot. This enables one type of oil to be generally used all year. In fact, when multi-grades were initially developed, they were frequently described as all-season oil. The viscosity of a multi-grade oil still varies logarithmically with temperature, but the slope representing the change is lessened. This slope representing the change with temperature depends on the nature and amount of the additives to the base oil.

The SAE designation for multi-grade oils includes two viscosity grades; for example, 10W-30 designates a common multi-grade oil. The two numbers used are individually defined by SAE J300 for single-grade oils. Therefore, an oil labeled as 10W-30 must pass the SAE J300 viscosity grade requirement for both 10W and 30, and all limitations placed on the viscosity grades (for example, a 10W-30 oil must fail the J300 requirements at 5W). Also, if an oil does not contain any VIIs, and can pass as a multi-grade, that oil can be labeled with either of the two SAE viscosity grades. For example, a very simple multi-grade oil that can be easily made with modern base oils without any VII is a 20W-20. This oil can be labeled as 20W-20, 20W, or 20. Note, if any VIIs are used however, then that oil cannot be labeled as a single grade.

The real-world ability of an oil to crank or pump when cold is potentially diminished soon after it is put into service. The motor oil grade and viscosity to be used in a given vehicle is specified by the manufacturer of the vehicle (although some modern European cars now have no viscosity requirement), but can vary from country to country when climatic or fuel efficiency constraints come into play

BruceP

Thanks, ivangene. I think I knew all that stuff. But it doesn't explain to my poor old brain why anyone would worry about 'protection' when the '0' is only the cold viscosity rating.

chsu74

^ Bruce,

You actually read that. I am waiting for cliff notes.

bkjwhipple

Here is what my indy said when I sent him the LN Engineering oil write up link. I hacked it apart to keep relevent info only so its a little choppy, but This shop knows their stuff. :-)

"mobil 1 is fine in your car. Your car does not have the pressures inside the engine that the older engines did. The zinc was for pressures in the valve train specifically the cam shaft to tappet. Since your car has smaller valve train parts the pressures are less and that is why I say what i did. and if your nervous us castrol syntec 5-50. It has more zinc than mobil 1"

ivangene

since we have the same indy I will also add that recently discovereed amoung us is evidence that the lifters (valve train specifically the cam shaft to tappet) are seeing wear on 3.6 vario cam plus that might be worth trying to prevent - the wear causes the center section to become mushroomed at the top and then the action of the variocam plus no longer works once the center section is press fit into the outter section (lifter becomes solid instead of slip fit outter and inner 1/2's)

sorry for the long read above, not sure about the W # and what makes it significant, there are a couple oil guru's around here that will pop in and explain that (i hope)

htny

The LNE link is nice

btw I've always wanted to try the 300v in a car, very popular in bikes, honestly I would like to try any Group V oil. now that I'm out of warranty finally my next fill will be ester based

anyone have an opinion (haha) on the moly content of these oils re: m96?

roadsession

My dealer - Herb Chambers Porsche - just filled Mobil 1 0-40
Now I have to worry about this too ???

roadsession

and then of course I see this ad on the top of the forum :

http://www.mobiloil.com/USA-English/....aspx?option=2

BruceP

No. You don't.

bkjwhipple

Yes we do, but that's from my east coast indy I got peeps everywhere! lol

Dharn55

I am certainly no oil expert, never took any chemistry. But I know at lower temps, below operating temps an 0W-40 oil has less viscosity than a 5W-40, and a higher viscosity oil provides more film strength and lubrication. So I believe that the 5W oil provides better lubrication at start up. Now if I was living on the north slope of Alaska, and starting my engine when it was -30F I would want the lower viscosity, but in the Chicago area I feel more comfortable with the 5W-40, and in the really hot temps the 5W-50.

I know that the dealer I bought my car from always used Mobil 1 0W-40, and they did the oil changes until the warranty was gone. However I am looking at my original owners manual (2000 996) and it DOES NOT LIST A 0W-40 FOR THE CAR! For synthetic oil (ironically it also gives a listing for mineral based oils) it lists for "generally higher than 50F" 10W-40, 15W-40 and 15W-50. for "generally lower than 50F" 10W-40, 10W-30 and 5W-30.

So explain the use of 0W-40 when it is not even listed in the owners manual. I think there may have been some TSB's that list 0W-40, I will have to look, but it ain't in the owners manual!

Dharn55

Checked the TSB's and found two from 2009 (both are listed as superseded, not sure why or by what) that list 0W-40 along with 5W-40 and 5W-50. They say for temps below 25C use the 0W-40.

What to do? What to Do? What to Do?

I am sticking with the 5W-40 and 5W -50 myself.

countrysquire

Well, since we're talikng oil, I'll put in my pitch for Schaeffer 9000 5w40. One of the highest HTHS specs in the industry and costs less than $5 a quart. I'll be doing an oil change tomorrow and will post the lab results when i get them back from Blackstone.