Subaru Ascent Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
932 Posts
Discussion Starter · #1 ·
Hi all,

I recently experimented with my 2011 Outback (EJ253) with some Liqui-Moly MOS2 engine oil additive. It's supposed to be a friction modifier to keep wear and tear down and improve miles per gallon, operating temperature lower, and quieter operation, especially at engine start.

This last oil change interval ran me from April to September 2018, 5000 miles. I don't have first-hand experience with MOS2 during winter on very cold startups.

Here's some pictures for comparison. Notice how it's chocolatey-brown. This could be misinterpreted as a head gasket leak where the coolant is getting into the oil on older Subarus (not the FB or FA series engines), so just make note of it.

Also, keep in mind that the total volume of your oil plus additives should not exceed specifications or damage could result to the seals among other things in your engine. For example, the can is 500 mL. Your example car (not the Ascent, just an example) needs 4.5 L of oil; so now you subtract .5 L of oil and replace it with the MOS2.

My operating temperature at highway cruise speeds is about 194F. I'll see if it is hotter without it, which would potentially indicate more friction. Stay tuned.
 

Attachments

·
Administrator
Joined
·
10,942 Posts
My operating temperature at highway cruise speeds is about 194F. I'll see if it is hotter without it, which would potentially indicate more friction. Stay tuned.


Just an FYI... the 2011 Outback (and the Ascent, IIRC), will regulate temperature to roughly 195°, +/- a couple degrees, during normal operation. So, you shouldn't see a difference either way. The cooling system will work less or work harder to ensure the engine stays at about the temperature you're seeing.
 

·
Registered
Joined
·
932 Posts
Discussion Starter · #3 ·
Cool. That makes sense. I have an OBD reader that I use regularly so I'll keep an eye on the Coolant temperature, too. If the cooling system is working harder, the coolant temperature should be higher than normal too right? (That seems to like the 196-198F area for highway cruising)
 

·
Administrator
Joined
·
10,942 Posts
Cool. That makes sense. I have an OBD reader that I use regularly so I'll keep an eye on the Coolant temperature, too. If the cooling system is working harder, the coolant temperature should be higher than normal too right? (That seems to like the 196-198F area for highway cruising)
Yep. It will vary a few degrees depending on what you're doing, the state of your antifreeze (you've passed the "lifetime" period on the original) and any air voids that may be caused if you do have a bad head gasket. It's part mechanical (water temp mechanical thermostat mounted on the bottom of the engine) and part electronic (fans, circulating valve, etc), but largely, it's the thermostat that controls actual cooling.
 

·
Registered
Joined
·
561 Posts
WS2 and HBN are also suppose to help with wear and tear and reduce heat.
I know they've tested it on heavy equipment and certain UTV gearboxes to reduce whine. Really cool stuff.

Tungsten disulfide (WS2) and Boron Nitride Engine Oil

http://www.techenomics.net/2016/09/want-boost-engine-oil-performance/


Boron Nitride (HBN) is similar but a lot pricer:

https://www.tandfonline.com/doi/abs/10.1080/02726351.2013.779336


From another thread:


Yes, I also noticed that hBN was less effective in this test as compared to MoS2. However, hBN did reduce wear compared to pure PAO(if not friction). I wonder what the reason for this is, does hBN not work well with pure PAO for example?

It easy to find studies were hBN has been found to be effective, for example this one where hBN was added to two different brands of 15W-40 diesel oil and was found to lower friction and reduce the wear rate by 58%:
http://www.jurnalteknologi.utm.my/in...view/2685/2022

Also I find this interesting: Rice team develops thermal nano-oil with high thermal conductivity and good insulation properties - Green Car Congress
Apparently addition of hBN increases the thermal conductivity mineral oil. Could this effect be of benefit in a car engine or not?

Furthermore, I stumbled upon this Henkel product, SLA 1710. Is this how hBN fluid is marketed to additive manufacturers (repackagers?):

https://tds.us.henkel.com/NA/UT/HNAUTTDS.nsf/web/754A2376005024588525759E0070BF73/$File/SLA%201710-EN.pdf

"Provides a revenue generator with a differentiated product against traditional graphite or PTFE lubricants by offering extreme pressure performance with friction reduction properties from the boron nitride"

"Provides cost-effective usage in finished lubricant to provide superior lubrication
performance, consumer confidence and repeat sales"
 
1 - 5 of 5 Posts
Top