String Trimmers

     I have the 224L Gas Trimmer.  Owner Manual says to use Husqvarna oil 10W-40.  A small bottle came with the unit, thx.  However, nobody in my area carries Husqvarna 10W-40.

     The manual states if I cant find it to use a four stroke petrol engine oil SAE 10W-40 at least API SG.

     I want to make sure I understand this right.  It sounds like it is recommending an oil normally used in automobiles SAE 10W-40 API SG, and not necessarily designed for small 4 cycle small engines?

     Ive never used a regular automobile engine oil in a small 4 cycle engine.  I just want to make sure I'm reading this right. 
     I don't want to wear out my engine or void any warranty.

    My only alternative is to drop down to a 5W-30 oil for 4 cycle small engines which is common and obtainable in my area.

     Thanks in advance for any assistance in advance.