LB7: oil is black in one day is this bad?
- Thread starter d-max joe
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what is the average milage you guys are changing oil on the deisels? im just reading averything i can at this point (never had anything deisel) & im looking to upgrade to a 08 or newer duramax in the near future. Im used to 3000/3500 on my gas engines
I ran a quart of sea foam for 25 or 50 miles before my last oil change and when I drained it it came out extremely black. Then I ran just a little bit of oil to flush out the left over black oil and sea foam in the bottom of the pan. Filled it with Mobile Delvac and after a 1,000 mile round trip pulling an 18 ft. enclosed trailer with a few dirtbikes and quads in it, the oil looked brown and not black still. I read of someone doing this before I did it and I really think that it cleaned alot of the old soot out of it keeping the oil clean longer. When it starts getting black faster again I will just repeat the process. I do not think it is abnormal for a diesel engine to have dark oil relatively fast and I don't freak out and change mine whenever it starts to get dark. I do however, think it is crazy to think that oil with soot in it can do its job as well as clean oil. It is simply not true, soot in oil has been proven to negatively affect wear characteristics inside engines and has even been blamed for premature engine failure in extreme cases. Cleaner oil is better, simple as that.
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I change mine anywhere from 10-12k, depending on the dash indicator. I send a sample out for analysis every time, and they say that is a good interval.
The oil comes out black, and new oil is only clear for 500-1000 miles, depending on my driving style. 290,000+ miles on the original engine, so it can't be that bad for it. I just use a high quality oil and a new filter every time.
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The oil comes out black, and new oil is only clear for 500-1000 miles, depending on my driving style. 290,000+ miles on the original engine, so it can't be that bad for it. I just use a high quality oil and a new filter every time.
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Black oil just means there is soot in it. Even though you do an oil change, there is still billions of soot particles and possibly some sludge build up that stays in the engine, that is why i like to run seafoam in the crank case before an oil change to help to strip the particles off internal parts and break down sludge.
When i first got our truck the oil was just changed at the dealer we bought it from(used) the oil was black by the time i got it home! Like jet black. I ran sea foam(one can) for 50 miles then changed the oil, 100mi later it was black again. I did a complete egr delete to my lbz, ran sea foam for 100mi and changed the oil again. I had been running mobil delvac 15-40, then switched to full synthetic mobil 5-40. I run seafoam before every oil change, and now after about 6 oil changes and no egr my oil will look choco brown after 1000mi and black by 3000mi. I really think the full syn mobil has better resistance to sludge build up and cleans better as it lubricates. That is just my opinion though, no scientific data to prove this, just a cleaner dipstick for more miles after a change.
So to get my oil to stay cleaner longer i :
Egr delete
Seafoam at every oil change for up to 100mi(can says you can run it constantly)
Full Synthetic oil
Now i change my oil at the earliest 5k(if towing all miles) 7k for mixed driving and 10k for all empty miles
This program has seemed to help, although im sure most will agree that the egr delete was the greatest compliment to the program.
When i first got our truck the oil was just changed at the dealer we bought it from(used) the oil was black by the time i got it home! Like jet black. I ran sea foam(one can) for 50 miles then changed the oil, 100mi later it was black again. I did a complete egr delete to my lbz, ran sea foam for 100mi and changed the oil again. I had been running mobil delvac 15-40, then switched to full synthetic mobil 5-40. I run seafoam before every oil change, and now after about 6 oil changes and no egr my oil will look choco brown after 1000mi and black by 3000mi. I really think the full syn mobil has better resistance to sludge build up and cleans better as it lubricates. That is just my opinion though, no scientific data to prove this, just a cleaner dipstick for more miles after a change.
So to get my oil to stay cleaner longer i :
Egr delete
Seafoam at every oil change for up to 100mi(can says you can run it constantly)
Full Synthetic oil
Now i change my oil at the earliest 5k(if towing all miles) 7k for mixed driving and 10k for all empty miles
This program has seemed to help, although im sure most will agree that the egr delete was the greatest compliment to the program.
Full synthetic is better to run it slicker then snot. And gives you better protection with the cold starts. I m a big believer in synthetics ive switch every thing over.
It's not the EGR, I havn't had one on my truck for about a year. I can almost hear my oil turning black when I pour it in it happens so fast.
Now thats funny right there....:roflmao:
Every LB7 i have changed the oil on, has had just as black of oil as my lbz and they dont have the egr bs, i cant help but to believe that by removing the egr the oil in my engine stays cleaner, unfortunately, i have never done an oil analysis, before or after, so its all just speculation
Whats not just speculation though, is my oil does stay cleaner for more miles now that i use synthetic, deleted my egr, and use seafoam before every oil change:hmm::dontknow:
My LB7 stays clean till around 2000 miles on the oil.
My LBZ also stayed clean for quite a while too.
I change oil every 2k miles, and thats how I cleane dup the soot in the oil.
My LBZ also stayed clean for quite a while too.
I change oil every 2k miles, and thats how I cleane dup the soot in the oil.
Yeah, I just bought my '03 and the guy said he changed the oil just before i picked it up and when I checked it a couple days later it was kinda black. Thought the guy was pulling my chain so I asked around and was told diesels get black after oil changes. Had no idea as this is my first one. So not to hijack the thread but what oils does everyone use? We sell Lucas Oil at the shop but I also have access to Amsoil and there's always Rotella but wanted to get some more feedback.
I deal with 4 lb7's and 1 lbz in my family, ranging from 85k to 246k. only one(lb7 ) stays clean. They all run the same oil pressure and don't consume oil at all, so I don't sweat it. I use valvoline cummins blue synth. in all my stuff. 5k change intervals.
LB7 with 225k stays clean up to 6k..like dark chocolate. Even when the EGR was connected it would stay clean for a couple thousand. Since the single bypass oil filter it stays clean longer. Under the valve covers this thing is spotless. I did do a several oil changes when the truck was new...500miles 1k miles and 3k miles. Not sure if that had anything to do with it. Always ran somebody's synthetic through it. I do not change oil sooner than 10kmiles.