Hi,
My 2001 Escape is supposed to have 5 - 20 weight oil.
I have been using Schaeffer synthetic. Lately my local supply shop only carries Schaeffer 5 -30. Would it be harmful to my engine if I used that instead of the 5 - 20?

 

Probably not. A fifteen year old engine probably has plenty of extra bearing tolerance by now from accumulated wear over the miles.

 

No. Manufacturer oil recommendations are based on achieving better fuel milage, you engine will run just fine on 5w30, 10w30, and even 20w50 but those heaviest weights would not be recommended for winter use and will definitely impact fuel milage.

 

Just an FYI - ours had a tick the few times we used something other than 5-20.

 

I upped my '06 to 5W30 when it was new because I.M.O. 5W20 is too darn thin for 100+F arizona summer heat..it has over 150K on it now and the engine still runs great...