Also, if I was in your situation, I would at least look into a programmer (after you get your injector/fuel problem fixed) and ditch the DPF-the fuel savings alone would be worth it-take your chances with the warranty.
6.7 cummins major fuel dullution in oil sample
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This truck has always had about 1-1.5 quarts extra when I change the oil. That's why I sent it in to blackstone to see what was going on. They showed everything was fine other than it shearing to a 30 weight which isn't really a problem for a diesel. So ive been scratching my head about it for the last couple years. I started thinking my it was soot from the egr. I called blackstone up and asked if they tested for soot content. They said no so I decided I would try a lab that does. The soot content wasn't really that bad. Ive seen worse. I spend a lot of time on cummins forum and everyone else has the same problem as me. And they send in a sample usually to blackstone from what I have seen and it comes back looking fine with minimal fuel. like 1.0 percent. From what I have heard the people that ditch the dpf and egr don't have the growing oil problem anymore. They also gain about 4 mpg. But the fact that this one lab is showing 10 percent fuel has me a wee bit concerned that maybe i have an injector problem starting to occur and that its not just the dpf/egr system. I just have mixed feelings about this truck.
dnewton3
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Originally Posted By: motor_oil_madman
This truck has always had about 1-1.5 quarts extra when I change the oil.
Now, if I understand your comment correctly, you're saying you always get 1.0 to 1.5 more qrts out than what you put in? Or, are you saying you always put in a bit extra?
Quick math in my head here, presuming you're getting out more than you put in. The ISB takes 14 qts or so for OCI right? And you get "about 1 - 1.5 qts extra" out? Would that not be 10%? Would that not be just about the same fluid volume as your 10% fuel dilution?
Perhaps the UOA and your OCI volume are trying to tell you something!
You're presumably still under warranty. Here is what I'd do:
Do an OCI immediately with some cheap dino oil. Then do it again about 500 miles later for a complete flush; put the issue to bed so that you can start "fresh". Then, put in some quality dino oil and run 3k miles; measure the exact amount that goes in. Then at the end of the 3k miles, do an OCI and take TWO samples from the same load, and then send them off to two different labs. Fuel dilution is pretty much undeniable and undebateable. Between the lab results and the OCI volumes, you should know if you have an injection issue.
If you have a dilution issue, I'd seek warranty help asap.
This truck has always had about 1-1.5 quarts extra when I change the oil.
Now, if I understand your comment correctly, you're saying you always get 1.0 to 1.5 more qrts out than what you put in? Or, are you saying you always put in a bit extra?
Quick math in my head here, presuming you're getting out more than you put in. The ISB takes 14 qts or so for OCI right? And you get "about 1 - 1.5 qts extra" out? Would that not be 10%? Would that not be just about the same fluid volume as your 10% fuel dilution?
Perhaps the UOA and your OCI volume are trying to tell you something!
You're presumably still under warranty. Here is what I'd do:
Do an OCI immediately with some cheap dino oil. Then do it again about 500 miles later for a complete flush; put the issue to bed so that you can start "fresh". Then, put in some quality dino oil and run 3k miles; measure the exact amount that goes in. Then at the end of the 3k miles, do an OCI and take TWO samples from the same load, and then send them off to two different labs. Fuel dilution is pretty much undeniable and undebateable. Between the lab results and the OCI volumes, you should know if you have an injection issue.
If you have a dilution issue, I'd seek warranty help asap.
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Even when I had uoa's done with blackstone the truck would make 1 to 1.5 quarts extra but they only showed between .5-2.0 percent fuel. Normal range. Now i decided to use a lab other than blackstone because i have seen lots of 6.7 reports but they are all blackstone reports. Most of the other guys on the internet forums claim the same thing. 1.5 quarts extra but no fuel dilution shown on the uoa. Later on I'll post up my three blackstone analysis reports to show how similar they are to the one that has 10 percent fuel. Im thinking it's had fuel dilution all along. That would explain the extra quart and the low viscosity.
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Wow-that can't be good for bearing or even cam life-if you are getting that much extra oil out those injectors need to be replaced or at least tested NOW-you are taking years off the life of the engine! I have heard that DPF equipped trucks were bad for fuel dilution, but nothing like this! I always keep a close eye on the oil levels of the CR diesels I drive & change fuel filters on a regular basis-only problem I've had was gasoline in the diesel pump ONCE, guess I've been lucky!
I learned this lesson a couple years ago when I started using Polaris. They use Gas Chromatogaphy to calculate fuel which is a more accurate (and costly) means of determining fuel dilution levels.
Blackstone figures fuel from viscosity and flashpoint. Look up the flashpoint of diesel fuel and you will see why this is such a poor means of determining fuel dilution.
I had a 03 powerstroke that always "sheared" the oil to med 30 wt but fuel was always fine. Then Polaris started using GC and fuel dilution went to 5-7 %. Wear metals always looked fine in all cases. Dyson and Polaris are the only two labs I know of that can come close on fuel.
I really wish Blackstone would upgrade their equipment because they are awesome to do business with and their customer service I have found to be superb.
Blackstone figures fuel from viscosity and flashpoint. Look up the flashpoint of diesel fuel and you will see why this is such a poor means of determining fuel dilution.
I had a 03 powerstroke that always "sheared" the oil to med 30 wt but fuel was always fine. Then Polaris started using GC and fuel dilution went to 5-7 %. Wear metals always looked fine in all cases. Dyson and Polaris are the only two labs I know of that can come close on fuel.
I really wish Blackstone would upgrade their equipment because they are awesome to do business with and their customer service I have found to be superb.
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Well they rechecked it. The only thing they messed up on was the tbn. They fixed it and now it's at 3.75. That makes more sense. So I guess the extra oil is actually fuel. After three years I finally found the answer. Amazing. Well atleast the wear metals aren't off the charts or anything. Copper is at 3ppm. Which means the bearings aren't taking too much of a beating. This extra fuel has to be the regen process. They inject fuel on the exhaust stroke and it goes down the exhaust and to heat up the dpf. The problem with that is that is some gets past the piston rings and causes cylinder wash and also goes into the oil. Im not really happy that blackstone has said everything is hunky dorry for the last 3 years when I have been running around with a quart of fuel in the oil. No wonder it thins out to a 30 weight. Luckily a diesel will still run just fine on a 30 weight. time for a programmer and exhaust system looks like.
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straight #2 diesel. ULSD that is. Yeah ive heard that bio diesel is worse for the oil and causes dilution of the oil. Causes worse mileage and power also. seems just like that ethanol [censored] they put into the gasoline.
Don't you just love all the new technology emissions makes the companies put in the trucks?
I would sell it and look for something else unless I was attached to it.
I would sell it and look for something else unless I was attached to it.
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The oil doesn't ever have a diesel smell to it. It just smells like carbon. Smells just like it would if a diesel truck just drove by.
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