You replaced almost 1/3 of your sump capacity during this oil cycle. That is a lot of oil for that Cummins, I pulled all over the country with my Ram and never had to add a lick of oil to her. But then I absolutely never idled the truck and always used full synthetic oil. It is not normal for that engine to be consuming that much oil. When was the last time you replaced the crankcase filter? It is supposed to be replaced every 69000 miles. If it hasn't been changed it is probably causing your crankcase pressures to run high enough to push oil out of your engine. The question then is, where has that 3 quarts of oil gone? I sir do know diesels and that Cummins 6.7 in particular.
Delvac 1300 17k mile; 2016 Ram3500 w/6.7 Cummins 143k miles
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I also should have asked what was your average fuel economy towing? That will give us a good idea how much work the engine was doing and if there was enough heat generated to cause the engine to use oil.
Wlslon, I never separated unloaded from loaded fuel economy... best I can figure is I had about 11000 miles towing and 6000 miles unloaded. it averaged out to slightly below 12. I think the oil usage was good... since its is a Cummins, it really isn't much work for it.. it runs 190 to 210 on the coolant and 190 to 220 on the oil.
Trust me, if you ever get the chance to pull a large RV on all the routes to Alaska and back, you will find out what your truck is made out of. FWIW I've been all across the USA pulling a RV and nothing in the lower 48 matches the workload the Alcan, the Dalton, the Cassiar, the Bighorn, and Yellowhead highways have to offer. I'm good with this truck, just like it is. Nothing to improve on, if you know what I mean.
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I had an '18 Ram CTD and coming from a Duramax/Allison, I disliked the standard transmission (68RFE iirc) with its "shift flare" torque management. That was a significant shortcoming in the drivetrain compared to the Allison or Ford's 6R140 TorqShift and is definitely something that could be improved upon. Do you have the Aisin transmission option?
negative... yeah, MOPAR needs to go the ten sped route, but it is debatable if they will. as it is it has that 68 with all it's inherent weirdness. lets put it this way, it is what it is and the truck will most likely outlast me, so I figure to live with it the way it is... I pull a large fifth wheel with it. it does that well enough.. if it ever craps out, it will get another trans.
A 13 SP is much nicer on the West Coast hills.
I agree but the 8 speed was used coast2coast. Lot easier to just flip the button and not have to move the stick. Loved the Super 10 also.
Never had the chance to drive a class 8 with an automatic.
I drove a 5 speed main and a 3 speed brownie. I prefer it over an air shift anything.
I have the Aisin transmission in my '17 HO Cummins Dually Ram. I have never experienced the "shift flare", I've seen a few owners of the 68RFE mention. I've had no complaints towing a heavy 5th wheel. The trans temps stay well under control. I don't think I've seen over 200° F, even climbing steep grades with the A/C running, in over 100° F ambient temps. at 36k GCVW.
Yes, as I said it's a 68RFE problem. If I were to do it again I'd do exactly what you did - get the Aisin - but it is a very expensive expense (it's an option) to just get near Ford or GM standard per (base level) transmission performance.
Aisin seems to hate an easy life, it flares and acts up until loaded. Mine flared ( still does to some extent), but put 5-10k load on it and it's happy as a clam.
Curiously, granted it is a single anecdote, my buddy hauled with a 68 for about 400k and has been just singing praise about the tranny. I don't know if it was reprogrammed or what, but it did function properly without failure or inconvenience until he moved on to a 5500 with a 69 aisin.
I personally will not use a filter for its "full potential" if there is a higher likelihood of failure. The aforementioned Donaldson and [so far] WIX has not failed on me yet, so I tend to run those as long as sanely possible.
I am curious about the consumption though, I used to add oil to old beaters when I was a kid, I knew where it went (puddles under the car). I had a new car with a defect that I added oil to, until the TSB work was done. But the rest, if ever consumed any amount would be always < 1/4 of the way within the safe zone on the dipstick. I can't possibly be this lucky, or do people react to oil consumption as "OK by design" and not look for issues to resolve the consumption?
Curiously, granted it is a single anecdote, my buddy hauled with a 68 for about 400k and has been just singing praise about the tranny. I don't know if it was reprogrammed or what, but it did function properly without failure or inconvenience until he moved on to a 5500 with a 69 aisin.
DBL7349 I would not hesitate to run for an abusive interval. However, 15k for the up to 2018, and 20k intervals are factory for current cummins models, and the factory spec filters look to be blend media at best. Filter intervals for many cars and motorcycles have been 10-15k non severe service for aeons, so filters have been trusted to work a lot harder than by a lot of us consumers. I've pulled filters off neglected 20-25k mi oci cars with them sludged, plugged and black, but intact.Is there an existing filter that could take that kind of mileage? Makes me think the original OCI could have been ok without the filter change. I realize my question could be self answered but not sure if i can stare at 50 UOAs from a website forum format. I want unfettered access to blackstones database
I personally will not use a filter for its "full potential" if there is a higher likelihood of failure. The aforementioned Donaldson and [so far] WIX has not failed on me yet, so I tend to run those as long as sanely possible.
I am curious about the consumption though, I used to add oil to old beaters when I was a kid, I knew where it went (puddles under the car). I had a new car with a defect that I added oil to, until the TSB work was done. But the rest, if ever consumed any amount would be always < 1/4 of the way within the safe zone on the dipstick. I can't possibly be this lucky, or do people react to oil consumption as "OK by design" and not look for issues to resolve the consumption?
3 quarts in 17,000 miles is nothing even if it had been run unloaded for the entire time. Being deleted it could burn a lot more and not have any effect as long as it is added when needed. Outstanding UOA.
I would have changed the filter also.
I would have changed the filter also.
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