Castrol HM 10w-30

[nbpt100]

I have a 96 Sable with the Duratec 24 valve engine. I bought the car used with about 45k miles on it. I put in Mobil 1 5-w30 and I found it consumed allot of oil 1 qt/ 1000 miles. The engine is clean and no apparents leaks. For the next several changes I switched to Mobil 1 HM 10w-30 and saw little difference in the consumption. I then tried the Castrol 10w-30 HM and saw the consumption nearly cut in half. I did notice a slight drop in fuel economy over the Mobil 1 products. Why does this product work better for oil consumption than the Mobil and what is the technical explanation of what may be happening? Will I get equivalent engine protection with the Castrol HM as I would with a non HM dyno oil? I did notice the Castrol HM is not Energy saving.

I appreciate anyone posting with some technical insight. Thanks.

 

[Camu Mahubah]

Does your car have oil leaks? Or is it burning oil?

 

[mikeg5]

maybe the thickness of the oil between the two. i know castrol like their oil a little thick and M1 is usually a little thin.. this is just a stab at this..

 

[TallPaul]

High mileage oil is good! Use it whenever you can. My preference is Maxlife (hint, hint,

)with it's 300 ppm moly and 12-22% PAO.