Density is also used for converting between volume and weight for export shipping purposes. In the USA oil is usually sold by volume (gallons) but in many parts of the world it is sold by weight (metric tons).
Density of motor oil
- Thread starter Patman
- Start date
I use density when filling and emptying. Chuck the oil pan on the scales and I immediately know the volume that came out. I want 5.8L in, I put my 6L container on the scales and weigh in 5.8L of oil.
Because I use cheap shop scales, I put the density in as the per kg price, and the scales then read directly in litres.
I know at the last service I put 5.80L +/- 10ml of oil in, so I know how much it has used in 10,000km down to perhaps +/- 20ml. Precise with sufficient accuracy and probably completely anal.
Because I use cheap shop scales, I put the density in as the per kg price, and the scales then read directly in litres.
I know at the last service I put 5.80L +/- 10ml of oil in, so I know how much it has used in 10,000km down to perhaps +/- 20ml. Precise with sufficient accuracy and probably completely anal.
Patman
Staff member
After reading all of the responses I’m still confused as to why the oil companies think that the average buyer cares about the density. People want to know the viscosity and the HTHS but I can’t see any reason why people would care that much about the density of different oils. Nobody here is saying they chose a particular oil because of its density value 
It seems like it’s something that should be in the SDS or somewhere else regarding the shipping aspect of the product but not in the technical data section. I hate that most manufacturers are making it harder to find the HTHS of their oils (but yet tell us the density!)
It seems like it’s something that should be in the SDS or somewhere else regarding the shipping aspect of the product but not in the technical data section. I hate that most manufacturers are making it harder to find the HTHS of their oils (but yet tell us the density!)With all the hype around non VII containing engine oils I’m surprised that the topic of non VS Newtonian fluids hasn’t been discussed.After reading all of the responses I’m still confused as to why the oil companies think that the average buyer cares about the density. People want to know the viscosity and the HTHS but I can’t see any reason why people would care that much about the density of different oils. Nobody here is saying they chose a particular oil because of its density value
Maybe I’m an outlier, but I look at the density of engine oils which lets me guess the VII content and HTHS.
As a side note, railways ship and charge by the ton mile in North America. Both volume in cubic meters and US gallons are stencilled on the rail cars along with the empty and maximum loaded weight of the car.
“286 loading” or 143 Imperial tons is the standard GVW of rail cars.
Add three feet of wet snow on top of a 7,000 foot train and suddenly you’re climbing grades at six miles per hour instead of ten.
While density can be useful for several purposes as noted in the posts above, it does not have much use for average buyers. Even for technical business purposes such as export shipping and quality control, more significant figures are required than the two figure values sometimes reported on a TDS. It is just one of those properties that has traditionally been reported to fill out a list of properties, like color.
Actually that is Specific Gravity. Density is mass per unit volume.
What is API gravity?
I believe that question was on Jeopardy.
I believe that question was on Jeopardy.
API Gravity is also a measure of density compared to water, but is the inverse of Specific Gravity, e.g., a higher API Gravity means a lower Specific Gravity.
For more information, see: API Gravity
For more information, see: API Gravity
yes the differences are small, yet easily detectable.
here's a list of 10W-30 ravenol oils, with their densities. the PAO full synthetics are the least dense.
RAVENOL TSJ SAE 10W-30 semi-synth low hths 0.858
RAVENOL Formel Standard SAE 10W-30 mineral high hths 0.859
RAVENOL Spezial Diesel SAE 10W-30 mineral high hths 0.859
RAVENOL UDT Ultra Duty Truck SAE 10W-30 semi-synth high hths 0.862
RAVENOL Low Emission Truck SAE 10W-30 semi-synth high hths 0.863
RAVENOL TRE Truck Resource Conserving SAE 10W-30 semi-synth low hths 0.854
RAVENOL Turbo Plus SHPD SAE 10W-30 mineral high hths 0.865
RAVENOL Formel Diesel Super SAE 10W-30 mineral high hths 0.859
RAVENOL Motobike 4-T Ester SAE 10W-30 full synth pao/ester high hths 0.851
RAVENOL SCOOTER 4-T 10W-30 full synth pao/AN high hths 0.852
I have actually used the density data when picking oils. If two oils have very similar and desirable characteristics I would then pick the more dense oil. I believe there is more protection there. This was based on data I reviewed some time ago but forgot the source.
Ali
Ali
Let’s not forget that grease and gear oils are sold by the pound in the U.S. still, largely. Not by the gallon.
But you said above that the weight changes per 1000 liters if the temperature changes, then later say if the temperature changes the weight remains the same. Conflicting statements. The latter is correct, a change in temperature does not change the weight, but it does change the volume and hence the density (ie, weight per volume)
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I've used the density specs for converting cSt to cP and vice versa, and as an input on pressure drop calculations (fluid dynamics calcs). Plus other people in industry may need to know the density for some kind of engineering calculation.
Mass, and therefore weight doesn't change with temperature. Density changes with temperature because volume can change with temperature.
What you said below is correct, but what you said before that weight changes with temperature was not correct. You have conflicting responses.
Your so sure that you are correct...lets just pretend you are to stop this.
Your right okay....happy now?
Do some research and prove it to yourself.
Search: "Does the weight of mass change with temperature"
Weight doesn’t change with temperature just as mass doesn’t either. The example of an overflowing container is a silly example.
Weight changes with gravity (acceleration) but that’s about all.
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