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Formula+ viscoty

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Old Jul 16, 2024 | 09:32 AM
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Default Formula+ viscosity

I just wanted to verify the viscoty of formula+. I have read several posts that state it's a 50 weight. Knowing there is a difference in motor oil and gear oil ratings are they referring to the formula+ with a motor oil rating or gear oil rating? I'm assuming it's a motor oil rating because a gear oil that's 50w would be extremely thin.
 

Last edited by dontdropit; Jul 16, 2024 at 10:58 AM.
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Old Jul 16, 2024 | 04:46 PM
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Originally Posted by dontdropit
I just wanted to verify the viscoty of formula+. I have read several posts that state it's a 50 weight. Knowing there is a difference in motor oil and gear oil ratings are they referring to the formula+ with a motor oil rating or gear oil rating? I'm assuming it's a motor oil rating because a gear oil that's 50w would be extremely thin.
From what I've read, it's a 50W motor oil.
 
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Old Jul 16, 2024 | 05:15 PM
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I believe it is about the same grade as SAE 50 motor oil.

I have no idea how much it weighs...
 
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Old Jul 16, 2024 | 05:24 PM
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It’s got to be close to 80W140 gear oil because that’s what they are pushing now.
 
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Old Jul 16, 2024 | 05:44 PM
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Maybe @BrandonSmith will chime in, he knows these things.
 
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Old Jul 16, 2024 | 06:23 PM
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It's a straight 50W non detergent gear oil. You don't want detergents added to a lubrication fluid in a transmission or primary that has no filter.

It's better that contaminates settle on bottom.

Might want to consider's synthetic version of Formula + if you ride in the winter and for sure in the hot Southern states.
 

Last edited by Jackie Paper; Jul 16, 2024 at 06:32 PM.
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Old Jul 16, 2024 | 06:47 PM
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Best I can do. @BrandonSmith can probably explain it.

Harley Davidson Formula+
Application: recommended for heavy-duty service in manual transmissions where the manufacturer normally recommends either engine oils or GL-1 lubricants.
Specific Gravity: 0.857
Pounds per Gallon: 7.14
Viscosity, ASTM D 445,
cSt at 40°C: 168.04
cSt at 100°C: 20.10
Viscosity Index, ASTM D 2270: 139
Brookfield Viscosity, ASTM D 2983,
cP at -26°C - 28,800
cP at -40°C - n/m
Pour Point, ASTM D 97, °F (°C): -60 (-51)
Flash Point, ASTM D 92, °F (°C): 507 (264)



Harley Davidson FORMULA+ Trans and Primary Chaincase VOA

(Mini VOA via Amsoil)

Petroleum based.

Ca 169
P 230
B 210
S - some
Zn - essentially none
No other elemental additives.

Vis. within SAE 50 range.

Listed as a GL-1, does test out as a GL-3.
 
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Old Jul 17, 2024 | 05:30 AM
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  1. I have no idea what viscoty is.
  2. There is no such thing as 50 weight (or grade) gear oil. The lowest SAE gear oil grade is 70W.
  3. If the above data is factual, Formula+ is SAE 90 gear oil. It does not contain the additives to be classified as an engine oil; if it did it would be 40W-60 engine oil.
 
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Old Jul 17, 2024 | 06:04 AM
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Brandon, if you compare Formula + drip count to 90W hypiod gear lube, you will know it's not 90W.

Now it does compare to 75W-90 synthetic gear lube made by Mobile 1.

Iinterestingly you say there is no gear oil thinner then 70W. You sure of that. We had couple dozen 55 gallon barrels of oil were I worked (Main machine shop NN Shipbuilding) of oils for machine lubrication.

Majority were gear oils.

In my post 6, I called it a gear oil and I used that term loosely since its non detergent since there no filter. I got the 50W from its drip rate being in the range of a 50W motor oil.

Is that wrong?

Very interesting that an oil engineer will tell you not to use a detergent motor oil in a transmission but for quite a few years, Harley said SYN 3 was number 1 choice.

Then a few years back , they suddenly started saying it was the second choice to use in their primary and transmission. That sure told me it's not the best or ever was for a Harley transmission or primary.

And they determined that by warranty problems.
 

Last edited by Jackie Paper; Jul 17, 2024 at 06:30 AM.
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Old Jul 17, 2024 | 06:14 AM
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Originally Posted by Jackie Paper
It's a straight 50W non detergent gear oil. You don't want detergents added to a lubrication fluid in a transmission or primary that has no filter.

It's better that contaminates settle on bottom.

Might want to consider's synthetic version of Formula + if you ride in the winter and for sure in the hot Southern states.
STOP IT.

OP, as state by others, you heard correct, it would be closest to an SAE 50 motor oil. See the chart below for a comparison to gear oil:

 
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