Black engine oil!?

[epartsman]

Does anyone follow the recommendation for engine oil weight listed on the back of the sun visors? It says SAE 30 above 40°F and 10W-30 below 40°F, with either recommended between 40-60°F. I have always run Rotella 15W-40 because everyone else does. I am thinking about changing to the SAE 30 in about a month or so in South Carolina for the long summer. Any comments about better performance or mileage?

Unfortunately my 09 doesnt have those stickers however I am going to check the TM for lubricants as if I can use SAE30 here in Florida I may get better performance and lubrication. I change every 3K, a rule that has suited me well as I have had vehicles that if they had no been totalled would have had over 300K miles on the original engine ( was t- boned and rear ended @ 240K and 260K).

To the original poster welcome! Dog head Mods both starter relay and glowplug resistor bypass to the 12V buss bar are a must! Read the TM's and act as if it has a million miles on it and go through everything, all fluids, filters, and repack the front wheel bearings. preventative maintenance is the key. Enjoy!

 

[idM1028]

Does anyone follow the recommendation for engine oil weight listed on the back of the sun visors? It says SAE 30 above 40°F and 10W-30 below 40°F, with either recommended between 40-60°F. I have always run Rotella 15W-40 because everyone else does. I am thinking about changing to the SAE 30 in about a month or so in South Carolina for the long summer. Any comments about better performance or mileage?

I bought my truck in NC and was there throughout the summer. I've always run Shell Rotella T 15-40W. Everybody I knew out there with a CUCV ran the same exact thing.

 

[safelyiniowa]

I know this is an old thread but I want to thank everyone who responded to OP. The black oil had me really spooked, nice to now it isn't a problem. I thought it might be a problem with the bypass valve in the base of oil filter casting. I have what appears to be a drain plug with heavy spring inside. That plug is hard to get our, not much room for a socket. So I was thinking maybe wrong plug, affecting when bypass valve opened, with no oil through filters as a result. When warmed up the oil pressure at idle is 1/4 way up, 15 psi I believe.

 

[bchauvette]

An old Diesel mechanic told me it is carbon residue and is actually a lubricant.

Yes it stains as in drop the filter into the drain bucket creating exclusive severe duty work clothes. Got tired of being asked what was wrong with my forehead

B.T.W. Scrubbing your forehead with Fast Orange hurts.

 

[swbradley1]

Not every diesel engine is like that. My Brother's JD450C dozer oil isn't black. I pull the stick every time I'm helping him and I run it and every time it looks brand new. No, I am pretty sure he doesn't change it every day. It is the only engine I have ever seen like that although the Deuce I sold the engine oil was still clear enough to see through after a few hundred miles. Then it broke the crankshaft. Coincidence? Sure.

 

[Keith_J]

I'm going to get flamed here..bought my truck in 2012 with 9009 original miles. Oil was black so I changed it at about 10k miles. I have not changed it again .

The oil cooler line up by the radiator has a class 2 leak, I've swapped out Viton o rings multiple times and it stops the leak for a day or two. So it consumes about a quart every 500 miles, I figure an oil change every 4000 miles is about right

it it has a shade over 17k on it now.

my 2k VW TDI always has black oil. But my MEP002A generator still has cleanish oil, just a touch of gray after 30+hours on the oil.

Back when CUCVs were new, we only changed oil when test results from AOAP said to do it. And that was almost never. 2-1/2 and 5 tons only got changed when injection pumps were bad.

 

[eme411]

oil change on a diesel should be like a religion , do them on time, every time , and use something good like Rotella and don't beat the **** out of it and it will run a very long time,
my 1008 is a 87 , did it's time in the Canadian Army , a buddy had it for about 6 years , I've owned it for 15 years , runs like a top 230,000 km, look after it ,

 

[98G]

I'm going to get flamed here... So it consumes about a quart every 500 miles, I figure an oil change every 4000 miles is about right

it it has a shade over 17k on it.

Are you changing the filter?

 

[bchauvette]

You don't get the benefit of draining all the dirty oil and a complete clean oil charge.

I'm going to get flamed here..bought my truck in 2012 with 9009 original miles. Oil was black so I changed it at about 10k miles. I have not changed it again .

The oil cooler line up by the radiator has a class 2 leak, I've swapped out Viton o rings multiple times and it stops the leak for a day or two. So it consumes about a quart every 500 miles, I figure an oil change every 4000 miles is about right

it it has a shade over 17k on it now.

my 2k VW TDI always has black oil. But my MEP002A generator still has cleanish oil, just a touch of gray after 30+hours on the oil.

Back when CUCVs were new, we only changed oil when test results from AOAP said to do it. And that was almost never. 2-1/2 and 5 tons only got changed when injection pumps were bad.