Amsoil 0w-40 vs 5w-40

[A_Harman]

Originally Posted by Buddyp
JAG, after reading your comment, I went to amsoil's page and looked up the differences. I googled everything, but maybe you guys can explain better. How does the descriptions (kinematic viscosity and such) correlate with the numbers.


Nice to see that you found the specs on AMSoil's site. They have very informative spec sheets. The critical number that is used to assess an oil's ability to protect an engine at high-speed, high-temperature operation is the HTHS viscosity, which is measured at 150 C. Since the 0w40 has an HTHS of 4.2, and the 5w40 is 4.3, I would say they are both safe to use, as SAE specifications require a min HTHS of 3.5 for 0w, 5w, and 10w-40 oils. You might see higher consumption with the 0w40, as the NOACK volatility is 10.9, and the 5w40 is 9.2. But even 10.9 is respectable. The 0w40 actually has higher kinematic viscosity at 100C, but yet it has lower HTHS. This is an indication that it has higher shear viscosity loss due to the presence of more viscosity index improver additive. The higher NOACK of the 0w40 also indicates that it has thinner base stock, and requires more VII additive to get the wide viscosity spread.

I think it would be worthwhile to run the 0w40 if you are cold-soaking in the north woods at -15F for days. Less stress on the cranking system for starting, and less oil pressure delay after startup.

 

[A_Harman]

Originally Posted by ofelas
FWIW, the 0w40 DZF cranked up as easily as my former 5w30 HDD fill, and built oil pressure much the same.

It's been -25c or so (without wind chill) these past couple days on the middle part of the ON-QC border.

Didn't use the Webasto, truck wasn't plugged in, just a couple hits of the grid heater & started the old girl up.

I did have to smack her into 4x4 all the way to the major hwy.


How do you like the Webasto when you do use it? I've been thinking about getting one (or an Eberspacher) for my old truck. It's much less grumpy starting on subzero days if the engine is kept warm. It has a lazy cylinder if I let it get that cold, and white-smokes badly for a couple of minutes.

 

[ofelas]

I rarely have access to an electrical outlet.

The Webasto is useful; 30 minutes in -40, and the grids don't even cycle when I start the truck, and instant warm air through the dash vents before I get rolling.

I prefer the Webasto to the Espar, as it had the option of a large rotary control knob that's easy to use with gloved hands.

I also have the Webasto exhaust pointed towards the fuel filter head.

 

[PiperOne]

I'll second Webasto over Espar (Eberspracher or whatever). Webasto's just run longer trouble free with less maintenance. We have a Webasto bunk heater (air not coolant) that has been running since 2011 and it routinely see's 1000 hours of use per year. All I've done to it is change the fuel filter twice..and at the start of winter I overdose the fuel tank it draws from with a fuel additive to kind of clean it out and lessen the amount of start up smoke. We remove the webasto's when we sell the trucks..send them out for a $300 re-fresh and they go back into new trucks. Espars...seems like you are always doing something to them (burner motors, screens etc).

 

[Eddddd]

Correct me if I am wrong. In order for an oil to be labeled 100% synthetic (not Fully Synthetic), they have to be synthesised and produced free of any mineral or crude oils. It essentially has to develop molecules from scratch, Can this be done with Group III basetocks? There are only 2 oils I know of labeled 100% synthetic. That is Motul and Amsoil SS. Just trying to understand the comment about Amsoil not being Group IV. Thanks.

 

[StevieC]

Originally Posted by Eddddd
Correct me if I am wrong. In order for an oil to be labeled 100% synthetic (not Fully Synthetic), they have to be synthesised and produced free of any mineral or crude oils. It essentially has to develop molecules from scratch, Can this be done with Group III basetocks? There are only 2 oils I know of labeled 100% synthetic. That is Motul and Amsoil SS. Just trying to understand the comment about Amsoil not being Group IV. Thanks.


Amsoil uses mainly Group 4 PAO basestocks with Group 5 Ester base stocks as their soluble additive carriers in their premium oils. In their XL and OE lines of PCMO's as an example they are Group III hydro cracked oils.
This is confirmed by the oils properties in the data sheets they provide and is also confirmed on the UOA's here where extreme mileages are run on these oils both in regular filtration and bypass filtration setups. (Premium oils)

Group III being hydrocracked can be labelled as 100% Synthetic or Fully Synthetic with the exception of Europe which has labeling laws concerning this.
Mobil sued Castrol over Castrol using the word synthetic on their hydrocracked oils and lost because Castrol proved that when you hydrocrack a crude oil it's changed at the molecular level and thus a synthesized oil is born that just isn't heavily refined crude any longer.

The reason benjy gets all bent out of shape along with a few others is because PAO and Ester basestocks are the holy grail to them and while this was a great thing when the additive technologies were lacking decades ago and using a premium basestock over a lesser basestock for better performance, it's not the same today and you can have a Group III hydro cracked oil with the right additives that will outperform an oil that is heavy on the PAO or Ester. He and the others want to live in the past and run around trashing brands like M1 and Amsoil that use Group 3 in some of their oils. There is no proof to his claims and the forum members have asked for this and none has been provided.

He is welcome to spend the $1300 or so to prove his claims, but from what we gather from the oils specs on their premium oils from companies like Amsoil you can almost work out which basestocks they are using just by that alone so it's clear enough he is unfounded in his claims with the others and the HD oils / Diesel oils are no exception to this.

EDIT: See 2 posts for some updated information below...

 

[kschachn]

Originally Posted by StevieC
Group III being hydrocracked can be labelled as 100% Synthetic or Fully Synthetic with the exception of Europe which has labeling laws concerning this.
Mobil sued Castrol over Castrol using the word synthetic on their hydrocracked oils and lost because Castrol proved that when you hydro crack a crude oil it's changed at the molecular level.

Just to be precise, it isn't "Europe" it is Germany. Anywhere else in Europe is the same as the US. And it wasn't a lawsuit since there was (and is) no law to sue over.

 

[StevieC]

Originally Posted by kschachn
Originally Posted by StevieC
Group III being hydrocracked can be labelled as 100% Synthetic or Fully Synthetic with the exception of Europe which has labeling laws concerning this.
Mobil sued Castrol over Castrol using the word synthetic on their hydrocracked oils and lost because Castrol proved that when you hydro crack a crude oil it's changed at the molecular level.

Just to be precise, it isn't "Europe" it is Germany. Anywhere else in Europe is the same as the US. And it wasn't a lawsuit since there was (and is) no law to sue over.

My apologies... I had referred to it as Europe here because I had read it here times over and didn't know it was only Germany.

As for "lawsuit" that is how I understood it but it appears it was a dispute that was adjudicated. I stand corrected.
https://www.stle.org/images/pdf/STL...tic%20Lubricants_tlt%20article_Jan10.pdf

 

[ofelas]

A_Harman - what injectors are you running on your 24v ?

 

[BrocLuno]

Well in this thing, I'm with TiredTrucker. Ain't nothing wrong with Grp III and the right additives.

Per the Op's original question. Some 5W-40's may be had with excess VII's. Almost all 0W's are mostly very high quality base stocks and a premium additive package. The slight difference in viscosity at 100c will change over time if there are a lot of VII's involved (shear down), so the argument is that a OW may be more stable over time. The UOA's are where you will find the answer to the basic question