We were recommeded to use the subject oil in a small diesel engine on-site. I have had two problems specifying the oil.

1. I guess the CC designation is superceeded, but haven't seen documentation on what the current is....CF or GF? or other. (i.e was this a diesel desgnation or an automotive?)

2. While I can go to the Walmart and buy 10W-40 for a car, most industrial oils are sold as 15W-40 or 10W-30. Is there a reason for this.

OOPS...I didn't realize I'd lose my subject when the message showed. the specified oil is API CC 10W-40.

W for winter; basiclly for cold starting lubrication down to about -30F

The OEM current recommendation; most quality product will meet CF, CG.

Try an industrial lubricant supplier.

The first C in CC stands for Commercial. The second letter is for "Moderate Duty Diesel and gasoline engine service." CA is for light duty Diesel, CB is for Moderate duty diesel, CD is severe duty diesel and CE is for Turbo-Charged heavy duty diesel engine service. I have ran into the same problem with only being able to get 15W40. This must be their favorite oil to sell in bulk. I got a letter from the oil vendor saying it was OK to use the 15W40 before I use it. Our diesel has a block heater, so it never sees a cold start. This was a easy call for them. The oil stays at 90f in stand-by condition.

I apologise for asking this question but I have seen this happen so many times where the OEM has a generic recommendation without understanding the operation environment. So here it goes did the OEM understand the temperature operating conditions eg lowest start-up temperature, When they made their recommendation? If so 10W-40 is avaliable as is 5W-40 and 0W-40 all API rated for use in heavy duty diesel engine applications. I think the latest API designation is CI-4. If you have an older engine you won't get the benifets that the "new" formulation is designed to give you.
Vickie we have quite a few diesel engines some are operated indoors and sit idle for long periods of time in heated buildings. They don't need a multigrade engine oil because they don't have the cold temperature start-up problems. The oem's still make the generic recommendation to use a multi-grade. Some other equipment needs the 0W-XX because the -40C/F makes it almost impossible to get the engines restarted after they are shut down for a short period of time.
While I'm on the subject...block heaters (at least the ones that I am familiar with) only heat the coolant that surrounds the cylinders. This has almost no effect on the oil that is in the base pan some 10-15 inched below the actual engine block. So when the oil pump starts up the oil is the same temperature as the ambient air surrounding the base pan. There are heaters that you can get to heat up the oil in the base pan - be cautions if you go this route the maximum watt/density should be kept low to avoid burning (coking) the oil.
regards
Alan.....

Vicky:
your assumption of CC being obsolete is correct.
CC was introduced in 1961 and was replaced by CE in 1987.
CE is now obsolete
CF-4 introduced in 1990 replaced both CC and CE
They are all for HighSpeed, four stroke, naturally aspirated and turbo charged engines.
A good reference for API classifications is API 1509 issue date I believe was 2002

This things happens when OEM´s does not update the recommendation sheets. Is pretty common to find this type of obsolete recommendations, specially with two strokes diesel engine manufacturers.

Unless cold, say below 32F starts are common, you should be fine with a 15W40 CH-4 or CI-4 rated oil. Since the only requirement that you have is CC, and no manufacturer specific certification, there is no concivable reason not to run a 15W40 except at low temps. Many, if not most passenger car 10W40's probably meet CC, but the CH and CI 15W40's are radically superior oils.

If cold weather is a problem, you could run a CH or CI rated 5W40. Probably the cheapest, (which you can find at walmart, if they don't have it, they can order it) is Rotella Synthetic 5W40. Another common one is Mobil Delvac 1, which is also avalible from CAT dealers as their OEM 5W40, and from some autoparts stores as Mobil 1 Truck and SUV 5W40.