Originally Posted By: KCJeep
If it's for your Jeep honestly I'd pick something thicker, like Pennzoil HM or Castrol HM or even Rotella 10w30. It will run fine on the two you mentioned though, I'd personally pick the Mobil of the two.
JMO.
Look at the PDS sheet of Havoline high mileage. The 5w-30 and 10w-30 are viscosity 12.0 @100 cSt. Castrol GTX HM 5w/10w-30 list viscosity 11.7 @100 cSt. When PQIA tested Castrol HM 5w-30, viscosity was 12.01 @100 cSt, and Castrol HM was the thickest of all the HM oils included in the test. Havoline HM was not tested.
Anyway, I did not know that the Havoline HM was that thick until I checked their PDS yesterday. The TBN for the HM was listed at 8.5 compared to the black bottle at 7.4, so the premium for the high mileage oil is worth it to me.