# Measuring oil volume using scale and density?

#### CeeMee

I got a 6 gallon box of Castrol 5W-20 for a good price.

I need to measure out 6 quarts, but don't have a graduated container to put it in, and I don't want to buy one.

My idea is to take the oils density from the PDS and multiply it times 12 pounds to get the weight of 6 quarts of oil. Or multiply the density times 32oz to get the weight of one quart.

The Castrol PDS I have shows a density of 0.848 for 5W-20, but it also says that 1 gallon weighs 7.063 pounds.

Water has a density of 1 and 1 gallon of water weighs 8 pounds, so if I take the 0.848 density and multiply it by 8 pounds I get 6.784 pounds which is different than what the Castrol PDS shows at 7.063 pounds.

Am I doing something wrong in my calculations.

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thats way to complicating it.
7lb x 1.5 = 6qt.

Still not sure how that helps you..

you dont have an empty anything you can measure with but have a 6 gallon oil jug.. sounds pretty hopeless

or you could just dump in a close amount by eyeball and check dipstick for level?

or you could use an empty 1 or 5qt oil bottle.

I guess what I really want to know is if both the density and weight per gallon are correct on the Castrol PDS, or if they made a mistake. It looks wrong but it has been a while since I was in science class (40 years). That is why I attached a copy of the PDS.

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10.5945 pounds. 7.063 divided by 4 X 6.

It would be much easier to buy a pitcher to measure. A plastic pitcher at Wally’s will cost very little.

Besides, what kind of scale would you use to weigh this?

A gallon of water weighs 8.34 lbs.

10.6 lbs should be good to go.

10.6 lbs should be good to go.
According to the PDS that's correct, take the 7.063 and divide by 4, it's 4 quarts in 1 gallon which is 1.76575 quart so now you have the weight per quart and you have 6 quarts so multiply those two numbers together, 1.76575 x 6 = 10.5945 which is basically 10.6 lbs. You will need to weigh your container empty first and then add the 10.6 lbs of oil into it.

If water weighs 8.34 lbs per gallon then it's 2.085 lbs per quart or 12.51 lbs for 6 quarts.

Why do something silly like buying a measuring cup from the dollar store when you can have all this fun solving for X and showing your work with strangers on the internet.

We always figured 7lbs per gallon for purposes of shipping bulk oil. Not exact, but pretty close. Use that, and you'll be close enough that you probably can't see a difference on your dipstick. Try also to remember significant digits from science class.

Got an empty 5 qt oil jug around? Fill it to where it would be when full, pour it in, then add as required to get the level on the dipstick where you want it.

We assure you, there's no kidding here at BITOG.

Coming from someone who has a minor in chemistry and has spent a large portion of my career in a laboratory of some sort, this is bordering on bizarre. Just go steal a measuring cup from the kitchen. Or use an old 1-quart oil bottle. Or a 5-quart one that is graduated. Or just guess and use the dipstick as has been noted.

Sometimes you just can't understand no matter how hard you try. Perhaps the answer is that you're a little early this week by joining on a Wednesday.

I guess what I really want to know is if both the density and weight per gallon are correct on the Castrol PDS, or if they made a mistake. It looks wrong but it has been a while since I was in science class (40 years). That is why I attached a copy of the PDS.

.
No mistake. I have to convert to metric for this defining density as d=mass/volume in kg/L.

7.063 lbs per gallon is 3.204 kg per 3.7854 L. 3.204/3.7854=0.8464 The SDS lists density at 0.848. Close enough.

We assure you, there's no kidding here at BITOG.
Right on . Just when you think it can't get any more weird .

If water weighs 8.34 lbs per gallon then it's 2.085 lbs per quart or 12.51 lbs for 6 quarts.

All my life I was told that a pint is a pound the world around. Suddenly that’s not right?

A gallon of water weighs 8.34 lbs.

Thanks. That answers what I wanted to know. If I use 8.34# for a gallon the density calculation works. I do not know why I got 8 pounds for a gallon. Maybe because a gallon is 128 fluid ounces which devided by sixteen is 8 pounds. I asked Google and it showed 8 pounds before but now it shows 8.34 pounds.

This is why the metric system is better. 1 cubic centimeter of water is 1 gram and 1 milliliter.

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Coming from someone who has a minor in chemistry and has spent a large portion of my career in a laboratory of some sort, this is bordering on bizarre. Just go steal a measuring cup from the kitchen. Or use an old 1-quart oil bottle. Or a 5-quart one that is graduated. Or just guess and use the dipstick as has been noted.

Sometimes you just can't understand no matter how hard you try. Perhaps the answer is that you're a little early this week by joining on a Wednesday.
Betty Crocker bowls for a buck at Dollar Tree …

Coming from someone who has a minor in chemistry and has spent a large portion of my career in a laboratory of some sort, this is bordering on bizarre. Just go steal a measuring cup from the kitchen. Or use an old 1-quart oil bottle. Or a 5-quart one that is graduated. Or just guess and use the dipstick as has been noted.

Sometimes you just can't understand no matter how hard you try. Perhaps the answer is that you're a little early this week by joining on a Wednesday.
Just make sure you use a measuring cup designed for liquid measure and not dry measure. It's is a real thing and the measurements are not the same.

All my life I was told that a pint is a pound the world around. Suddenly that’s not right?

I think they meant a Pint cost you one Quid - back when the old adage was coined

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