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Topic: Oil consumption rate (Read 1645 times) previous topic - next topic

Oil consumption rate

I began to wonder, what is a "normal" consumption rate of engine oil, as in using (burning) rather than leaking the oil?

I found this chart.  I am not sure I am using it correctly, so if you should want to apply it to your coach, it may be important that you do more research on the rates shown in this table.   

from this web site, Hello, We have a QSK60 CUMMINS diesel engine SN 33156638 operating - JustAnswer

I read, for example, that the use of one quart in 500 miles would be acceptable for an M11/ISM.  I frankly had no idea.  Does that sound right for the usage rate?  So I called......

A Cummins service center and they told me that no oil use is normal, certainly not at 500 miles and you could expect an engine with even a million miles to use only a smaller amount.

I wondered about that, so I talked to Cummins Customer Care.  He explained that there would be usage, and especially with these engines with the turbo, for at boost of 35 pounds it would force some blow by.  I more or less interpreted that using a quart in 1500 miles might be normal.  But he had another comment.

On the dip stick for the ISM, there are two marks.  The engine is full at one and oil should not be added until it drops to the second mark.

Beyond that, a senior service technician said that in the 2001 timeframe, maybe more, there were some 295 and 270 coaches with the wrong dip sticks.  I think there are numbers on the dip stick that you can use to check whether you have the proper one.

There is a good thread related to this from 2009, oil level dipstick.  Bret speaks to the need to calibrate the dip stick and Gary B. an oil use in an 8.3 of 2 qts in 3 - 4,000 miles.

Perhaps this will help a newbie think about this topic and observe the usage rate. 

cheers, Mike
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: Oil consumption rate

Reply #1 –
I ran many different diesels, from the Detroit 238 up to a Cummins 400.  The big commercial engines, not the ISB or ISC., but the ones you would find in a over the road tractor trailer.  Jump seated a lot - I drove the same truck every day and various different night drivers drove it at night.  One thing I found was that drivers tend to add oil if it was below the full mark, like 1/2 or even all the way down to add.  If no one was driving my truck during the slow season, it did not use oil, and did not use oil until it was ready for a oil change.  It would sit right there at the 1/2 mark daily.  But if night drivers were running it and saw it down to the 1/2 mark, they would add 2 quarts every night and then it would get blown out the breather while they were running it.  I would ignore it the next morning and they would come along the next night and add oil again and blow it out the breather again.  Saw that happen over and over and over.  My Cummins 5.9 6bt does not use any oil.  Only time it needs oil is at oil change time.
1994 U225
build #4514

Re: Oil consumption rate

Reply #2 –
I use no oil on my coach.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Oil consumption rate

Reply #3 –
Cummins seems to feel, for warranty purpose, oil useage above the listed numbers is when they might consider a warranty repair with pressure from the customer IF all other conditions are met.

My ISM500 like most, uses no oil, home to Nac, return then Black Hills, SD and back, zero oil useage, then I change oil and all filters.  Mileage shows 91K.
Dave M

Re: Oil consumption rate

Reply #4 –
The only oil used in Forrest has been Chevron Delo 15W40 for the engine, genset and hydraulic.  There is no oil consumption by the Cummins C8.3 325 in roughly 40,000 miles driven over the past 9 years.  I was told not to switch brands when I purchased the coach from Foretravel.
Peter
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Oil consumption rate

Reply #5 –
251,235 miles on my m11 oil change every 10,000  no useage very little blow by
95 U320 SE
07 GMC CANYON

Re: Oil consumption rate

Reply #6 –
Pat's observation fascinating.  It makes sense given what Cummins told me, do not add oil until down to the second mark.    The coach we bought uses Delo 400 and it is used for the generator, not sure about the hydraulic slide.  I do not know how to judge any blow by amount, but I see no oil on the concrete where I park so I guess none left to drip out if it is blowing by.

As to the admonition in the thread I referenced earlier, I checked the oil level after two quarts were added and sure enough, on the dip stick it is quite overfilled (I assume you put the dip stick all the way in to measure).  Now to figure how to get it back to the full mark, not over.

I noticed too that new oil very quickly becomes pretty dark, not like in my gasoline pickup.  I read somewhere though, or Mike Rodgers told me one time, that is normal for a diesel.  Hmmm.
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: Oil consumption rate

Reply #7 –
My 8.3 has 6K on it since oil change, dip stick showed add, added 1/2 gallon, now at full where it usually is after change.  This is normal for my engine. Change again will take place at about 12 K, with oil analysis..
Gary B

Re: Oil consumption rate

Reply #8 –
Quote from: Michael & Jackie –
I noticed too that new oil very quickly becomes pretty dark, not like in my gasoline pickup.  I read somewhere though, or Mike Rodgers told me one time, that is normal for a diesel.  Hmmm.
The black is because of the soot exhaust.  It is normal and happens with all diesels.  Gets black almost immediately.  Soot is the reason you need diesel spec'ed motor oil, such as Delo 400 or Rotella T, which is designed to hold the soot in suspension.  If it wasn't held in suspension it would plug everything up and not run well.

On your dip stick, you need to get it calibrated.  You should call Cummins Customer service at 800-343-7357 and tell them your engine serial number and ask exactly how much oil your engine holds, including the filter.  Next time you change the oil, put it all in except for one gallon.  Put you dip stick in and find out where your low mark would be and mark (score it) it if needed.  Then add the last gallon and again check your dip stick and mark it if it is not correct.  That would be the full point.  Put a mark half way between the low and high marks.  That would be you add point.  Normally a diesel will find it "happy" spot after a oil change, usually a quart or a little more low, and it will stay there.  That is where I leave mine until it gets lower, and then I will add whatever is required.

Oh, the hydraulic slide probably uses ATF Dexron transmission.  HWH sells some that does not have dye.  That way your carpet in the compartments can not become blue stained.
1994 U225
build #4514

Re: Oil consumption rate

Reply #9 –
Quote from: Gary Bouland –
My 8.3 has 6K on it since oil change, dip stick showed add, added 1/2 gallon, now at full where it usually is after change.  This is normal for my engine. Change again will take place at about 12 K, with oil analysis..
Gary B
Gary,
It can vary.  I'd keep a eye on things and watch underneath for leaks.  I almost think every engine has a personality.
1994 U225
build #4514

Re: Oil consumption rate

Reply #10 –
Pat, I really enjoyed your first post, it aligned exactly with what Cummins Customer Care folks told me.  Let it go down to the add mark before add, not try to keep it to the full mark.

Then your second post expands on the first and so I wonder.  Where does the oil go?  I mean, I guess, why does it leave for a time and then "settle down" at some point and not just keep going away?

I like the comment about each engine having a personality.  I gather in all this that engines do use oil (burn or drip), contrary to what one truck stop mechanic told me, and some see it settle down and level out, others see it go down to the "add" mark by the next oil change. 

I think this discussion should be valuable to newbies especially.  Maybe a few others too, so thanks to all that contributed. 

I will add, if you are a newbie, be sure to read Brett's report about cooling the turbo in the October issue of FMCA magazine.  I have been "overdoing" it on both warm up and cool down, being a bit too cautious.

cheers and have a great weekend,  Mike

Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: Oil consumption rate

Reply #11 –
Pat, As we all do I do a pretrip oil check each day we travel and my engine is very consistant. The only variation I have noted is that after a long storage the oil level is always high, I think that is self explanatory.I end up with all the oil drained into the pan.
Gary B
 ,  I 

Re: Oil consumption rate

Reply #12 –
Quote from: Michael & Jackie –
Where does the oil go?  I mean, I guess, why does it leave for a time and then "settle down" at some point and not just keep going away?
Takes time for all that oil to drain down into the oil pan after you turn the engine off.  And where else does it go, when its running?---  It evaporates, and it gets blown out the breather hose (aka elephant nose) that hangs down under the engine and ends up all over your nice clean  toad.  It can also burn, and you really don't want that.
1994 U225
build #4514

Re: Oil consumption rate

Reply #13 –
Quote from: PatC –
It evaporates, and it gets blown out the breather hose (aka elephant nose) that hangs down under the engine and ends up all over your nice clean  toad.  It can also burn, and you really don't want that.

Any little oil leak....what a mess it makes on the toad. Even with the cover we have it can get messy back there. We still have to take care of a couple small leaks.  Can you believe I had a bit of oil or vapors leaking from the dipstick of all places. Think I have taken care of that one.

Roland

1993 U280 4341
2010 Jeep Liberty
The Pied Pipers
 

Re: Oil consumption rate

Reply #14 –
Never had to add oil between changes. Have 120,000 miles on the odometer.
Felix and Gail Mathieu
99 U320
Jeep Liberty CRD
Build number 5522