Another LSJr drive by…

[SubieRubyRoo]

“It’s important to use the proper viscosity designed to work with alcohol-based fuels because high fuel dilution will lower the oil’s viscosity. High fuel dilution can change the oil’s viscosity from 20w-50 to 10w-30, thus reducing the wear protection. So, in high-performance engines, you want all the protection you can get while turning high-RPM and not compromising the oil’s wear protection.

One would think if fixing the W rating of used oil was this simple, that oil companies would work with auto manufacturers to ensure a minimum amount of fuel dilution. Waitaminute…

Selecting The Right Oil For Your E85-Powered Application

E85 has different properties than normal gasoline. We look at why you need to use a high-quality engine oil when running E85.

www.enginelabs.com

 

[RDY4WAR]

Alcohol has a very low freezing temp (-173°F for ethanol, -143°F for methanol) and thus has a significant impact on CCS/MRV. It's actually the 30 grade side that's misleading here as the boiling points of ethanol (174°F) and methanol (149°F) ensure both are evaporated when measuring KV100. The KV40 would definitely be impacted. This would be relevant to a drag engine where the oil rarely sees >150°F.

Let's say you have a 20W-50 with a KV40 of 155 cSt. A drag engine on E85 can have upwards of 10% dilution. That's sufficient to drop the KV40 from 155 cSt down to 86 cSt, a typical KV40 for a 10W-30 oil.

So I don't see anything wrong with his statement except that a KV100 couldn't be accurately measured with alcohol dilution.

 

[Jetronic]

But alcohol dilution come through the piston ring pack and the alcohol s in contact with the hot cylinder walls and ringlands. Yet some alcohol still gets through so in practice the kv and HTHS will be impacted even if we can't measure it accurately.

I don't see any real issue with his statements either.

 

[SubieRubyRoo]

My point was, how could it affect the winter rating? Ppl on the board have been told that if you mix say a 0w30 and a 10w30, the oil will still perform roughly equal to the higher number (10 in this case) because there are still parts of the oil that will solidify? Plus, throw in the fact that the W rating can slip a grade worse (so 5w30 acts like a 10w30)… and so I’m just genuinely asking if the dilution actually improves the winter rating.

 

[Jetronic]

My point was, how could it affect the winter rating? Ppl on the board have been told that if you mix say a 0w30 and a 10w30, the oil will still perform roughly equal to the higher number (10 in this case) because there are still parts of the oil that will solidify? Plus, throw in the fact that the W rating can slip a grade worse (so 5w30 acts like a 10w30)… and so I’m just genuinely asking if the dilution actually improves the winter rating.

I don't believe that people mean mixing 0W-30 and 10W-30 doesn't affect the winter performance, but you can't be sure you're getting a 5W-30 out of it, and we can't test it either. So assume you still get 10W-30 winter performance and be safe.

I mixed some 2-stroke oil with a vegetable oil once and just because I could I threw it in the freezer at 0F. The vegetable oil by itself would turn into a solid above freezing already, but the mix was still quite fluid at 0F, just cloudy.

 

[4WD]

We all need to be extra vigilant to spot the LSJ gotcha moments!
If we don’t - he’ll be plugging Valvoline R&P B4 you know it