Originally Posted by
fiestamk2
ive used 10w.40 for nearly 3 yrs of owning the car and works great,gets regular changes as well.i did however use the millers 5w.30 and it didnt go down very well.we dont rag the car me and the missus use just to get around to work do the shopping and for the kids and ocasionly go out places.but 10w.40 has never give us problems.i think its how the car has been treated to be honest
Well there's no two ways about it, 10w/40 IS damaging your engine. The thicker oil can't escape through the rings or stem seals as easy so it wont burn as much oil, however, it also isn't lubricating the lifters or the crank as well as what 5w30 would.
I find that the zetecs do drink oil, I'm on my 8th zetec engined car, the only one that I have that doesn't drink oil is the car I have now.
When I researched it, the zetec-se are supposed to wear the 4th ring easily, unsure why, poor design/cheap manufacturing possibly?