I had a small oil leak meaning that I had to add 1/2 of oil between my 3k oil/filter change.
Was using Castro Oil Conventional 10w30.
When changing the oil last week I noticed that the leak looked to come from the crankshaft area or that side near the oil pan. The oil pan gasket was replaced a about six months ago but I did support the engine on that side while changing the timing belt, crankshaft seal, water pump, valve cover gasket and spark plug seals in January. With that said I may have created a very small leak in the oil pan gasket during that replacement.
During my recent oil change I remembered that I didn't change the camshaft seal due to lack of time (over 150K). So I called Advanced auto parts and picked up a camshaft seal. After that repair; I decided to use Castro High Mileage 10w40 due to my above mentioned small leak and the fact that it's summer is TX.

This daily driver does two hours of highway driving in 90-100+ heat.
Watching mpg with this tank of gas because I normally get 320 with 10w30 non HM.
I will say; I can tell a difference with High Mileage oil-engine really runs smoother.

Comments are welcomed.