2008 Dodge Ram 3500, 11k miles, RT6

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Still towing travel trailers. Some in mountainous terrain in warm weather. 11k miles on this oil fill. Added particle quantifier and truck hourmeter readings to the new UOA. Polaris comments: Flagged data does not indicate an immediate need for maintenance action. Continue to observe the trend and monitor equipment and fluid conditions. OXIDATION is at a MODERATE level, which may be due to extended drain interval or high operating temperature. Viscosity is MODERATELY HIGH. Causes include contamination, oxidation, incorrectly identified viscosity grade, or adding a different viscosity grade to the component. VISCOSITY INCREASE may be due to lubricant oxidation. Please provide missing application and sump information. Lubricant and filter change acknowledged. Still have lubricant oxidation, despite having the crankcase ventilation filter and EGR valve replaced about halfway through the OCI. Maybe it could be that the oxidation occurred before the repairs were made? Adding the Redline oil supplement didn't help anything, either. KV100 has once again increased out of grade, just as much as before, and on a shorter interval. I think the oxidation occurs early after an oil change, then slows down. The UOA at 182k had oxidation of 28 on a 20k mile interval, and the new UOA at 226k has oxidation of 23 at 11k miles. Soot is safe at 1.7. I think I will continue with 10k OCI's, and keep the filter in for two intervals. I have run Fram Ultras for 20k miles before without trouble. TBN was still strong. 14k miles seems to be the limit for TBN. Will continue searching for a reason for the oxidation. Currently have Motorcraft Super Duty in it, which is a syn blend, so I don't expect it will do any better than RT6. I have also disconnected the EGR valve to minimize EGR. Maybe it will help, but I can say that drivability has immediately improved. The engine no longer stumbles on every gear shift.

Dodge-UOA.PNG
 
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IIRC Cummins says the oil should be changed if the viscosity increases 2.5 cSt over the new oil viscosity. You have the soot under control, so I think your approach of monitoring at a 10k interval is a good idea. Is your check engine light on since you unplugged the EGR?
 
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Alot of guys un-plugged the EGR with good results. It seems like there is always some exhaust that squeaks by though. Having said that I tried unplugging the EGR and found it made my truck surge a little, mostly in reverse. Trying to hook up tp trailer was kind of scary. On the Cummins forum I found out that it didn't happen to everybody just a small percentage of folks with 08-09 trucks. It seem or was concluded it may have had something to do with the current flash on the truck. I just said screw it and plugged mine back in. The last flash on my truck was the J35 flash back in 2010. Haven't unplugged again though. Also the forum experts said that unplugging de-rates the truck appx 70HP, but there were some pro/con arguments about that. Just passing on info I've learned since having my 2008. Best to you.
 

A_Harman

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Yep, the check engine light is on, but at least I know the reason for it. Unless another fault code appears. I'll keep checking with a scanner. I haven't notice any lack of power since unplugging the EGR valve. Fuel economy is the same. I have run about 1300 miles since, and towed a trailer on a short run and the engine ran smoothly the whole time. I'm taking a longer run this week. If it continues to run fine, I will leave the EGR unplugged until the next oil change, so I can see the effect on the UOA.
 
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That's good, most of the guys running unplugged reported slight mileage gains, not big numbers mostly in the range of .5 to 1mpg. It was said the J35 flash i mentioned was to help with mileage also, and small correction to the lie o meter for mpg. I have slightly bigger wheels and tires (275/70/R18) and I haven't done any software corrections for it, so odometer is off slightly but I've always gotten decent mpg results empty or loaded by hand calc and using GPS miles traveled.
 
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Interesting that iron PPM/M is higher on a noticeably shorter run.
Originally Posted by A_Harman
If it continues to run fine, I will leave the EGR unplugged until the next oil change, so I can see the effect on the UOA.
That will be interesting to see! Without having ever looked (or remembered, at least), I'd expect that oxidation _might_ increase some since EGR's job is to lower combustion temps. Maybe not, though, if that heat doesn't normally translate particularly into the oil. Thanks for posting!
 
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Cut open and post pics of that Fram Ultra after you get to 20k miles, would like to see how it looks inside compared to a synthetic media Donaldson DBL7349 or Fleetguard LF16035 after that many miles.
 
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Over on the tdi club, someone is having similar issues with ck4 rotella t6 and oxidative thickening with an early 2000s tdi running 10k interval I believe. Eager to see the motorcraft results. Thanks for sharing!
 

A_Harman

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Originally Posted by Dodgetracker
That's good, most of the guys running unplugged reported slight mileage gains, not big numbers mostly in the range of .5 to 1mpg. It was said the J35 flash i mentioned was to help with mileage also, and small correction to the lie o meter for mpg. I have slightly bigger wheels and tires (275/70/R18) and I haven't done any software corrections for it, so odometer is off slightly but I've always gotten decent mpg results empty or loaded by hand calc and using GPS miles traveled.
Yes. I have found that the mpg meter is optimistic by about 20%. Is there a way I can find out what flash is in the ECM without going to a stealership?
 
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I'm really not sure n that one. I've never heard of anyone doing it. I only know mine because it was a recall to have it done. I believe dealership is the only route though. When dealerships flashed these trucks, they were putting stickers saying what flash under the hood up front somewhere. Mine had it but has since faded.
 
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