Got Sludge?
- Thread starter Ron Nielson
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Yeah it was more of a “general post” for guys who think more is better for trucks with a dpf. Not really directed at you
I'm not sure I buy the additives extending fuel system life argument. I've been through my fair share of injectors (I have a weak spot for the LB7), and tried everything under the sun to extend fuel system life. The only thing that had any measurable impact was two stroke oil will help a failing FPR to not stick and limp that along a while longer. The only true solution is the SAC style injectors (which are stock on the LLY and newer).
My parents have never used additives in their rigs, and my mom's 2006 Cummins is on the original injectors & CP3 at over 300k miles. My dad's 99 Cummins is on the original injectors and 2nd VP44 (original control board failed a couple years ago) at over 200k miles, though that is a relatively low pressure system so not a fair comparison.
And using oil analysis is the way to go. Oil analysis regularly shows 12,000 mile changes are just fine on my LB7 swapped Suburban, and my race truck (loose rings, etc.) needs changed around 5-6k per Blackstone Labs.
My dad always changed his Cummins at the "severe duty" 3k mile recommendation, and we thought it should go farther, so we sent a sample to Blackstone, and they said nope, don't extend the interval. Somewhat surprising considering the exact same oil (Delo 400) is happy at 12k miles in my Suburban, but totally spent at 3k in the 99 Cummins. Though that poor Cummins has a ton of blowby.
My parents have never used additives in their rigs, and my mom's 2006 Cummins is on the original injectors & CP3 at over 300k miles. My dad's 99 Cummins is on the original injectors and 2nd VP44 (original control board failed a couple years ago) at over 200k miles, though that is a relatively low pressure system so not a fair comparison.
And using oil analysis is the way to go. Oil analysis regularly shows 12,000 mile changes are just fine on my LB7 swapped Suburban, and my race truck (loose rings, etc.) needs changed around 5-6k per Blackstone Labs.
My dad always changed his Cummins at the "severe duty" 3k mile recommendation, and we thought it should go farther, so we sent a sample to Blackstone, and they said nope, don't extend the interval. Somewhat surprising considering the exact same oil (Delo 400) is happy at 12k miles in my Suburban, but totally spent at 3k in the 99 Cummins. Though that poor Cummins has a ton of blowby.
I have always felt the same way. The only thing I have seen that makes me question that now was an discussion on The Diesel Podcast. A panel member through out there that Biodiesel has higher moisture content. So the higher blending of Bio in Diesel is going to cause more fuel system issues.
While I haven't looked into that claim. It does sound logical. It makes me consider running a demulsifying additive.
Cummins have always been hard on oil 3k is a little lower then I would of thought necessary. I think 5k is what we did without UOAs
My opinion on this is that it is very true. My cousin is a tractor mechanic and they have changed fuel pumps just because the machine was sitting over winter or summer with bio in the system. Makes the fuel system rust.
Is he a Deere mechanic? We have had a bit of issues with our Deere dozers fuel systems.
I have never felt one was better then the other really. Wide spread fuel system issues wasn't an issue, so the filters where doing an adequate job of removing enough water to prevent damage by the suspensioned water. However if the claim is high moisture in the Bio is the issue then the filters are not adequately doing their job anymore. I would suspect water in suspension at whatever level is the problem now and we need to do more to drop it out. Demulsifying additives seem to of aways been more widely recommended by Bosh and ETC. Just my thoughts...
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He has a private shop But John Deere is primarily what he works on. As far as i know its happened on others too. Some of the excavation guys around will refuse to run bio in their excavators.
Just wanted to share this with everyone. Take a look and tell me what you guys think.
Source: https://www.youtube.com/watch?v=fu7PlRsqMyA
Depending on the application 3k miles is excessive in both directions.
They are right the dilution both in solid and liquid along with heat kills oils abilities to function properly.
Engine load seats piston rings.. heavier and more sustained the load the faster they seat
When I ran my LMM hotshot and my Freightliner with 8.3 Cummins hotshot, after 10-12k miles you'd see a drop in MPG.
Blanket Oil consumption statement was rather high, for dmax anything more than 1qt per 10k miles is excessive
A lot of engine failures can be exasperated with lack of oil.. heat thins oil out reduces oil pressure and allows for metal on metal. Generally why you measure oil pressure after the last place to get oil. As it will be first to loose oil if any of your "controlled leaks" get bigger.
I disagree with thinner oil is better mentality and need to change every 3k as a general statement. On the other hand thinner oil is easier to push thus less parasitic loss of power/efficiency makes EPA happy
The LQ4 in my suburban has ~463k on I've pretty much neglected it, ~40k miles to an oil change.. I got it with 251k I run 10w40 or 15w40 conventional any 30w blend trips low oil pressure light when I got it.
As for the US Navy doing predictive failures and regimented oil analysis about the 1940s he's correct. Having done those tests, we test for dilution (10% fuel was general blanket limit for peace time operations)
Soot PPM was different per application
And viscosity test compare to documented fresh sample
Of the engines I've lost, most were lack of keeping oil cool to keep the pistons cool, the next common failure was cracking #4 main web which showed up via a drop in oil pressure and or coolant in oil if it ripped far enough to get to the water jacket area of the cylinder walls, and wiped mains #2 and #4
Never did figure out why I ripped main webs with main studs
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After producing and running ASTM certified biodiesel for a decade, I like this guy.. Whenever possible, I suggest running some B20 to lube and clean the system. You'll hear and feel a difference. It's just better fuel .
On the oiling, my only lesson of late is never run synthetic on new rings because they won't seat properly. Besides that, the stable viscosity advantages across climates and operating conditions of synthetic is unbeatable for normal high performance usage. Just not that first fire IMO.
Sent from my SM-S901U using Tapatalk
We already have a thread on this one
I am considering getting my diesel oil analyzed by Blackstone but it one of those things. Do I really want to know, am I actually going to do anything about it? 2 years and 3 oil changes ago I was thinking the same thing and decided it wasn't worth it lol
Oo shit. Didn’t see this thread lol. I had the oil checked from blackstone at the end of 2022. Everything came back great, having 115k on the odometer. I plan on doing it again soon. On the next oil change. It’s nice for me to have as much knowledge as I can. So I can at least have an idea of what’s going on in the engine.
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I think Easy-E said it best in Boys-N-The Hood.... "I looked at my car and said Oh brother, I will throw it in the gutter and go buy another..." 
You just quoted him! He said “Don’t quote me “. Shit… now I quoted him. 
My '96 Impala is about to get an oil change and that will get analyzed. I am going on 2 years with the same oil. Only like 2k miles at the most.
My only comment when it comes to these outrageous 10K or higher oil change intervals is, "Oil is cheap compared to rebuilding an engine".