摘要 |
<p>A lubricant containing (a) a synthetic base oil composition having an overall kinematic viscosity of at least about 4.8x10-6m2/s (4.8 cSt) at 100oC and a viscosity index of at least about 110; (b) a dispersant-viscosity modifier; and (c) a sulfur-free functionalized hydrocarbyl-substituted phenol detergent provides improved valve train wear, with longer drain intervals, to heavy duty diesel engines.</p> |