Liqui Moly Reduces Gas Mileage

[walterjay]

I used a can of Liqui Moly halfway through my oil change on my SantaFe. I had an immediate drop of 1.5 mpg. I ran the mix for almost 2,000 miles so I was able to track it and the drop was consistent. I changed the oil back to straight QSUD 5-30 and had an immediate increase of 1.5 mpg.
Has anyone else had a similar experience with LM. What could be causing this? I have four cans of it now and not sure that I want to use it.

 

[paulri]

LiquiMoly makes oil additives plus a line of motor oil. Which one were you talking about?

 

[walterjay]

Liqui Moly MoS2 Anti Friction Engine Treatment. Part #2009. 10.1 oz container.

 

[paulri]

I used MOS2 in my Highlander and got the best MPG I've ever had in it, although it was only 0.2 MPG better. But I wasn't sure that it was enough to cover the cost so I haven't used it since, especially since that difference is probably well within the margin of error, and could be covered by many other external factors.. But I sure haven't seen a drop when using it, that's for sure.

 

[Davejam]

A full can is likely overkill.
Having said that, i'm not sure your data point is significant without some additional detail.

 

[raburn2906]

My experience is just the opposite, always had better fuel economy in my F150 when using it; nothing groundbreaking, but about a 3% increase. I've used it in a 2011 Sienna at work and had an increase of about 5% in fuel economy.

 

[dippschtick]

Rumor is MOS2 will increase the viscosity of your oil. IDK.

lubro-moly mos2 oil additive and viscosity

Does anyone know to what extent, if any, lubro-moly mos2 oil additive will affect oil viscosity? I've added a full can each to my Accord and Miata which use 5w-20 and 5w-30, respectively. Unrelated to my above question, but intriguing to me regarding the the topic of mos2, I recently took the...

www.bobistheoilguy.com

 

[Trav]

I have four cans of it now and not sure that I want to use it.

Door hinges, put some in an oil can, it is good for parts that slide like a vise and threaded tools like spring compressors. Just don't put it in an engine.

 

[kschachn]

I’m not sure you could even pour it out of the can if it altered the viscosity so radically that you would see this magnitude of fuel economy change.

Measuring real-world fuel economy changes and being able to attribute them to an isolated variable is an impossible task. Even if someone is under the illusion that they kept all the other variables constant they have not.

 

[Silver]

Door hinges, put some in an oil can, it is good for parts that slide like a vise and threaded tools like spring compressors. Just don't put it in an engine.

Dang.

 

[JTK]

The 10oz / 300ml bottle? Like said, I think there's something else going on. How the vehicle was driven, ambient conditions, fuel used, etc.

FWIW, I'm running Liqui Moly #2009 in my hemi ram. My plan is to alternate 2009 one oil change and Lubegard biotech the next. I got decent mail order deals on multi packs of these products. Total waste of $ perhaps. Got the cam/lifter thing on my mind is all.

Still getting ~22mpg average over the tank with my daily driving of the Ram. With or w/out the LiquiMoly.

 

[bullwinkle]

Seems like in large doses it tends to sink to the bottom of the sump and stay there-maybe it‘s making the engine work harder? Any increase in oil or engine temperatures?

 

[kschachn]

Seems like in large doses it tends to sink to the bottom of the sump and stay there-maybe it‘s making the engine work harder? Any increase in oil or engine temperatures?

If it caused that much drag the oil would have a very high temperature. All that energy from combustion that isn't going down the drivetrain has to be going somewhere, and if it's going into the sump it isn't necessarily going out the radiator either.