Engine oil question

[jaydee325]

The first number of a motor oil is the oils WINTER rating, it is not an abbreviation for "weight" and it relates specifically to the oils cold-flow properties and measured resistance at a specified temperature and into sub-zero ranges. Winter scale specs can go into more detail than a standard SAE test @ 0C.

A 5w40 offers superior cold-flow properties compared to a 15w40, but at operating temperature both oils provide the same viscosity and will protect the same AT TEMPERATURE if they have the same additive pack (same brand oil). The colder it is outside the slower your oil is going to pump.

Anyone who has started a vehicle in cold temperatures have experienced a slow start and have probably heard someone say the oil is "almost like honey". That means it is more viscous.

5w40 is more viscous below freezing, the winter rating is specifically relating to cold flow characteristics. This means a 5w40 flows like 5 weight oil would flow if it were chilled to 0C. It is "40 weight" at 100C. It does not mean it is a "5 weight" when cold. Many are confused about this.

Synthetics change the game and you can get away with running a heavier winter number. The improved flow characteristics of synthetic allow the oil to be run year round.

 

[GManBart]

I am thinking of using Shell Rotella Diesel engine oil.

My Kubota manual calls for 10w-30 engine oil.

I see the Rotella T6 Diesel oil in a 5w-40.

Can I use the 5w-40 in place of the 10w-30 oil/what is the difference?

I live in CT, so I operate in all 4 seasons, including cold winters.

I just looked at a Kubota B7800 manual, and it lists a range of temperatures and shows that both 10w30 and 10w40 are acceptable in all of them. Substituting a 5w40 won't hurt anything because the only difference is that it will flow better at low temperatures (a good thing).

I'm switching all of my newer machines over to T6 in the next month or so...before it gets cold.

 

[DarkBlack]

So much information and misinformation...
I love oil threads

 

[arrow]

The first number of a motor oil is the oils WINTER rating, it is not an abbreviation for "weight" and it relates specifically to the oils cold-flow properties and measured resistance at a specified temperature and into sub-zero ranges. Winter scale specs can go into more detail than a standard SAE test @ 0C.

A 5w40 offers superior cold-flow properties compared to a 15w40, but at operating temperature both oils provide the same viscosity and will protect the same AT TEMPERATURE if they have the same additive pack (same brand oil). The colder it is outside the slower your oil is going to pump.

Anyone who has started a vehicle in cold temperatures have experienced a slow start and have probably heard someone say the oil is "almost like honey". That means it is more viscous.

5w40 is more viscous below freezing, the winter rating is specifically relating to cold flow characteristics. This means a 5w40 flows like 5 weight oil would flow if it were chilled to 0C. It is "40 weight" at 100C. It does not mean it is a "5 weight" when cold. Many are confused about this.

Synthetics change the game and you can get away with running a heavier winter number. The improved flow characteristics of synthetic allow the oil to be run year round.

Not to confuse the issue but 30w or 90w applies to the "weight" of the oil. The "w" in multi viscosity I've heard as both "winter" and "weight".with the implication that it is 5 weight at early flow or that it is a "winter" designation at cold temps. There are some who still believe Husqvarna is owned by Electrolux if I had to be analogous to the subject.

 

[arrow]

So much information and misinformation...
I love oil threads

Which is which?

 

[Sodo]

The ones that say differences between oils are barely detectable is information.
The ones that say differences are significant (in normal engine usage) is misinformation.

Not referring to hot-rodded engines.

Two things are for sure.

1) Clean oil is better than dirty oil.
2) enough oil is better than not enough oil.

 

[TomSeller]

I'm switching all of my newer machines over to T6 in the next month or so...before it gets cold.

Same here. Switching to Rotella T6 from T5

 

[Soundguy]

The ones that say differences between oils are barely detectable is information.
The ones that say differences are significant (in normal engine usage) is misinformation.

I disagree.

There are measurable differences in pour point and flow characteristics between different grade oils.

You should be able to take a sae 30, 15w40 and 5w40 into a lab, and in a blind test, be able to show which oil is which due to pour and flow characteristics and viscosity index.

The differences are quite detectable, quantifiable, and measureable.

 

[TSO]

I'm moving away from Rotella T6 and back to Mobil 1. My PowerStroke doesn't seem to like the T6, as the injector noise is noticeably higher with the Rotella.

I actually just picked up a bunch of Mobil Delvac ESP 5w40 synth... I'm due for an oil change in my Massey, so I'm looking forward to seeing how she likes the Delvac.

 

[GManBart]

I'm moving away from Rotella T6 and back to Mobil 1. My PowerStroke doesn't seem to like the T6, as the injector noise is noticeably higher with the Rotella.

How is it in the Massey?