M1-HM is API-SL. Why?

[john_pifer]

It appears that the M1 HM variant is their only gas engine oil that doesn't carry the latest API rating (it's API-SL rated).

Why is that?

I am aware that just because an oil carries the most recent rating, that doesn't necessarily mean it's better than oils with an earlier rating.

Just curious.

 

[LeakySeals]

M1 HM a thick 5w30 with extra wear additives for high mileage engines. So it doesn't make the API's energy conserving catalyst requirements for SN.

 

[BISCUT]

Originally Posted By: LeakySeals
M1 HM a thick 5w30 with extra wear additives for high mileage engines. So it doesn't make the energy conserving catalyst requirements of SN.


That's what I was told by my mechanic as well. Bad eco HM oil!!

 

[tommygunn]

Probably due to ZDDP content being too high for SM/SN. They also lack the ILSAC starburst.

Also note that GC is also SL and not ILSAC.

The low ZDDP limits only apply to 20-30-wt oils. The xw40's are allowed to have more zinc/phos in them, which is why M1 HM 10w40 *is* SN

 

[Quattro Pete]

Exactly right, tommygunn!

 

[john_pifer]

I noticed that my local Auto Zone just started carrying the 5W-20 version of this oil, too

 

[mshu7]

Our local Walmart has 5-qt. jugs now as well. I'll probably try it soon.

Has anyone else tried it yet?

 

[john_pifer]

I don't plan on using it, as my Tacoma has had M1 or M1-EP since I drained the FF @ 3K.

However, if you look around, you'll find it's generally held in high regard around here.