Just got my oil report back and my viscosity was 79. The upper normal level is 78. 4,000 miles on the John Deere 15/14. The rest of the report was excellent with no insoluables found. They said it was no big deal. WHat controls the viscosity of oil? Why would it be a little higher this time? Thanks!
Viscosity is 79.....
- Thread starter roperteacher
- Start date
- Status
JHZR2
Staff member
huh? 79/78? maybe my brain just isnt in gear, but for engine oil, at temp viscosity should be roughly 5-20 cSt, depending upon viscosity and life.
Is there a way you can post your report in the diesel UOA section for us to look at? It would give us all a better idea with all the numbers.
JHZR2
Staff member
yeah. Is this engine oil or hydraulic fluid?
Hey there, sorry, here is the numbers from the report
79.0@SUS Viscosity 210'F Normal= 69-78
Cst Viscosity at 100'C is 15.27 Normal=12.7-15.3
This was a blackstone report.
79.0@SUS Viscosity 210'F Normal= 69-78
Cst Viscosity at 100'C is 15.27 Normal=12.7-15.3
This was a blackstone report.
Lets start from the top. What kind of vehicle, how many total miles on the vehicle, what are the driving conditions of the vehicle (i.e., highway, farm roads, stop and go, etc.) I believe you stated the oil is John Deere 15W-40 and that it had 4,000 miles on it at the time you changed it. How many months did it take you to go those 4,000 miles?
Now, start at the top of the UOA over in the left had column and list what they say going down. Kind of like this:
Iron - 29
Copper - 10
Tin - 0
Do this from top to bottom so we can read everything. Then we can try and give you the answers you are looking for.
Now, start at the top of the UOA over in the left had column and list what they say going down. Kind of like this:
Iron - 29
Copper - 10
Tin - 0
Do this from top to bottom so we can read everything. Then we can try and give you the answers you are looking for.
2007 Dodge cummins 5.9 68000 total miles. Oil was in the truck 2 months. Daily driver about 10 miles to work. Gets up to running temp by the time I shut down to and from work. On weekends it's my rodeo rig, pulls Large 3H living quarters horse trailer. 12-13,000 pounds.
Aluminum 3
Chromium 0
Iron 9
Copper 1
Lead 1
Tin 0
Moly 83
Nickel, Magnese, silver, titanium, = 0
Potassium 3
Boron 103
silicone 3
sodium 3
Calcium 2962
Magnesium 94
Phosphrus 1092
Zinc 1344
Barium 0
Fuel 0
Antifreeze 0
Water 0
Insoluables .2
Aluminum 3
Chromium 0
Iron 9
Copper 1
Lead 1
Tin 0
Moly 83
Nickel, Magnese, silver, titanium, = 0
Potassium 3
Boron 103
silicone 3
sodium 3
Calcium 2962
Magnesium 94
Phosphrus 1092
Zinc 1344
Barium 0
Fuel 0
Antifreeze 0
Water 0
Insoluables .2
There you go. I see absolutely nothing wrong with this report. Considering the vis number they listed:
Cst Viscosity at 100'C is 15.27 Normal=12.7-15.3
I would say you were right on spec. Did they happen to list a TBN number anywhere? Looks like this oil is doing a good job for you.
Cst Viscosity at 100'C is 15.27 Normal=12.7-15.3
I would say you were right on spec. Did they happen to list a TBN number anywhere? Looks like this oil is doing a good job for you.
roperteacher,
The viscosity is on the upper end of normal. Metals look fantastic and I would be very pleased. I see nothing of concern and you could probably run this oil much further but I would verify with a TBN test in the future. Like Johnny says I think this oil is doing a fine job.
REDDOG
The viscosity is on the upper end of normal. Metals look fantastic and I would be very pleased. I see nothing of concern and you could probably run this oil much further but I would verify with a TBN test in the future. Like Johnny says I think this oil is doing a fine job.
REDDOG
dnewton3
Staff member
I concur with Johnny and 'Dog.
I'll add this -
If you're going to be doing UOAs, then stick with one brand/grade of oil. It will reduce variability in your UOA reports. Further, since you only mentioned months of use, but not miles, it's a bit hard to determine the full exposure. It's often important to know the severity of use, the lenght of service, and such.
I suspect, given the wear numbers, you could go much futher on the oil. However, a TBN factor is going to be essential in making that final determination.
I'll add this -
If you're going to be doing UOAs, then stick with one brand/grade of oil. It will reduce variability in your UOA reports. Further, since you only mentioned months of use, but not miles, it's a bit hard to determine the full exposure. It's often important to know the severity of use, the lenght of service, and such.
I suspect, given the wear numbers, you could go much futher on the oil. However, a TBN factor is going to be essential in making that final determination.
- Status
Similar threads
