You are basing your decision of the use of 15W on the capability to start.

Unfortunately, you should be basing your decision on the ability to lubricate at 0F.

Take a bottle of 15W and put it in your freezer. Take it out the next morning and try to pour it. There is no possibility of finding such oil acceptable for flow at that temperature.

When you complete this experiment, you'll be answering your own question.

As far as fleet trucks use, no company will ever get upset if you put Lucas Oil Stabilizer in the oil. I personally like Lucas in all of oil changes . . . it does prevent the oil from thinning out during high temp driving, i.e., climbing hills, or driving thru Arizona in summer.

As far as other additives go . . . . MotorKote is awsome . . . could actually see the difference in the temperature, and I can attest to MotorKote making my bearings last longer than they should have. I puchased a used Peterbilt with a Cummins N-14 engine, and I stuck with what the previous owner used. He swore by Motorcoat, and had switched from Lucas to Motorcoat exclusively. You can put both in. Motorcoat is similar in schedule as Slick 50, but is supposed to be differently compounded without the harmful stuff. I haven't seen it at WalMart, but it is now available in most truckstops. For a car diesel motor (or gas), you would probably have to find a Flying J to get the quart size, as most places sell it to truckers by the gallon.

I have no problems with the idea of using Lucas (which is excellent) or MotorKote in any of my vehicles, including the 300D.

As far as oil goes, Chevron Delo 400 (in the blue bottle) is the thickest 15/40 oil out there and is great stuff. Right now I'm using Mobil Delvac, which is a blended oil . . . picked it up because it was on a special price . . . .my engine seems to like it just fine, but usualy go for the Delo 400 or the Castrol.

Mainly, keep your oil clean and change it regularly . . . . no matter what brand/combo you use and your engine should last forever.

you realize that the engine uses a positive displacement pump to move oil? viscosity doesn't matter to the oil pump for flow.

until they find out what you're doing!

it also makes it foam.

no its not, its terrible!
from their own website! "MOTORKOTE does NOT blend with the base fluid (oil)."

exctept for the last line, piccolovic, thats all terrible advice!

Has anyone used the Kilatrol additive in their diesel yet?

I hear it really clears things up, but has not been sufficiently tested.

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It may not matter to the oil pump, but do yourself an experiment and see how much oil will flow from a 1mm nozzle after the oil came out of the freezer.

The owner's manual specifically says to NOT use any additives.

Jim W.

Has anyone used the Kilatrol additive in their diesel yet?

sounds like a romance cream

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

What do you mean by "blended"?

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1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

http://www.fuelly.com/sig-us/40601.png

I'm not picking an argument, here, I'm honestly asking a question. How long after the engine cranks do you figure it takes before the oil has been heated by the engine itself, so the external temperature is no longer a problem?

My own personal reckoning (My car sees sub-20F temperatures only about 3 weeks out of the entire year) is that if a bearing or other moving part lacks proper lubrication immediately after startup at idle, it'll heat up faster due to the friction. There will be SOME oil being shot into where it needs to be even with diminished flow rates due to temperature, and that oil will be heated up very quickly (since it's a thin coating at any given time) by the moving parts. As that hot oil descends through the system and recirculates, it warms up its neighboring teaspoons of oil as it passes by them. By the time the car's idled for a minute, I figure things are starting to break loose and flow, and since I never pounded the engine in the meantime, the damage ought to be minimized.

That's why I don't start any engine cold and fly out of the garage without letting it warm up 2 or 3 full minutes if it's cold outside and 1 full minute even in the summer. I figure the warm up period lets the oil start flowing more freely as it gets up to operating temp and letting it warm up at idle reduces the number of RPMs therefore the amount of wear per minute until things are up to temp.

Yes, this argument is completely negated by the total idiot-proof simplicity of just putting thin oil in for cold weather and forgetting about it. But... for those of us who haven't taken that step, I'm thinking that what I'm describing here might help minimize the harm. That's my personal thinking. Opinion?

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~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

it doesnt matter to me, the driver does not do the pumping and the engine makes over 100psi within 1-2 seconds of running.

The question is whether the 100 psi is sufficient to move paste though the oil supply system............??

It might be adequate, but, personally, I'd rather have syrup.

It's your engine...........do what you wish.

The other aspect is, has damage already been done at 1 to 2 seconds. The other is that pressure is measured at one point. Is oil flowing in other critical areas. I don't have any experience with synthetic oils in diesel engines. I would trust them though. I do use synthetics in a couple of my gas engines. I do see a difference in gas milage. So, if my diesel dosen't leak, I'll be using some type of synthetic oils.
Tom

Perhaps, but perhaps not. The oil is designed to leave something of a residual coating on everything it touches even after the engine has been off; specifically for this purpose; to provide lubrication during the critical start-up period before the system takes over. This coating, at least in some oils, lasts from a few days to a week or two before it dissipates to the point of not working effectively. I've never seen a study on our specific oil selections but this is a fairly common oil property. So, you've got the residual coating helping to lubricate things during the first few seconds until the pump takes over.

Secondly, and perhaps less importantly, when the engine is cold-started under these circumstances, it's a reasonable assumption that all the metal in the engine is freezing cold, and is therefore ever so slightly contracted... even if it's just nanometers... from its operating-temperature environment. The metal expands ever so slightly as it gets up to the extremely hot combustion temperature, and it is at that most-expanded state that the oil must still provide enough lubrication to prevent metal-to-metal contact and wear. So, while the engine is freezing cold -- there's the ever so slight influence of the metal not being up to combustion temperature helping to increase the tolerances in a lot of the places where metal-on-metal contact would occur; particularly, I would think, between pistons and cylinder walls. So, if it only takes a minute or two to get the oil flowing sufficiently to ensure lubrication, I'm guessing that the residual oil and the cold metal help to minimize the damage that's occurring, if any is.

The people who put videos online of running engines with no oil, and then dumping water, sand, cement, etc into the crankcases, generally get at least a few seconds of normal operation as the residual lubricity wears off before the painful effects of their experiments start to be seen. On my coldest starts when I didn't change the oil weight, I'm gambling on the oil getting where it needs to be before those "few seconds" are exhausted. I'm sure this is allowing cumulative wear, but I think it is probably minimal compared to the life of the engine. Not really the difference between 250,000 miles and 500,000 miles before a rebuild. Maybe 250,000 vs. 251,000.

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~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

OK, then explain the purpose of the anti-drainback feature on most oil filters. In other words, I ain't buying it. Also, the surrounding metals contract with the cold also. Also, if you search most of the wear occurs during startup.
Tom

Anti drainback purpose: every little bit helps. That leftover lubrication was never intended to be perfect or long lasting. It's a crutch. Also I don't want oil picking up dirt in my filter and then returning to contaminate the rest of the pan even more.

Ain't buying it: that's fine with me. If I'm wrong I'd rather be responsible only for my own damage. I'm just describing the things that have influenced my personal decision.

Surrounding contraction and search results: agreed. I'm not denying that there's more wear done at startup under these circumstances. What I'm asking is whether that quantity of wear will ever amount to anything remotely significant in the engine lifetime. My personal two cents is that I doubt it. I have no quarrel with anyone more cautious than this. I'm just saying I never heard of an engine that died of this specific cause.

__________________


~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL