Amsoil said no to mixing weights

[aircooled]

I asked on the Amsoil site if it was O.K. to mix to different weights of the same oil. (10w-40 and 20w-50 Motorcycle synthetic)

They did not recommend it.

I asked Mobil this same question last year and they said it was fine.

Why or why not?

 

[rg200amp]

There is no need to mix. Use whatever weight the engine specs.

A 10w40 works best when its mixed with more 10w40, not 20w50.

You could* run mixed weights with no real issues. Its just that there is no reason. If your trying to use up the last quarts of oil sitting around then mix it no worries. If your buying new oil, just get one weight.

 

[Liquid_Turbo]

mixing occurs everytime you switch viscosities anyway.

 

[d00df00d]

As I understand, mixing is fine if the chemistries are very similar.

In some cases, though, two different weights of the "same" oil actually have very different formulations. In that case, mixing them is not the best for protection/performance (although it definitely won't blow up your engine or anything).

 

[Shannow]

Second what Doodfood states.

Amsoil might have sufficiently different chemistries (maybe across their range) that mixing them will be not as good as either alone.

 

[Titan]

I had a Vulcan 2000 (2053 cc V-twin, wet clutch with straight cut gears), which shifted best with AmSoil 20-50 and 10-40 mixed half and half. UOA's were stellar.

I recommend it, because I don't have to cover my you-know-what, and it worked well in my application.

 

[Titan]

I had a Vulcan 2000 (2053 cc V-twin, wet clutch with straight cut gears), which shifted best with AmSoil 20-50 and 10-40 mixed half and half. UOA's were stellar.

I recommend it, because I don't have to cover my you-know-what, and it worked well in my application.