Originally Posted By: ET16
I just got an '02 Cougar with this engine, and I was wondering what oil might go well with it. I had a Taurus with the 3L version of this engine that ran everything well.
I read, though, that the 2.5L had some oil problems with the early engines that lead to a redesign of some oil passages. Anything that I need to look out for?
The 2.5L duratec has 1/2 as many return passages in the head compared to the 3.0L. Those who put 2.5L heads on the 3L block have to address this issue IIRC. It's been over 6 years since I've played seriously in the Contour and Duratec world.
At high RPMs, oil will "pool" in the heads as it cannot return fast enough. The recommendation was to run 1/2 a quart to a quart overfilled if you were going to run your Duratec powered Contour in the curves, especially long RH sweeping curves.
If low on oil, at high RPMs during a RH sweeper, the oil pickup could begin to suck air, which isn't good for your bearings. So those who downshifted to charge exit ramps with a low oil level were in for a nasty surprise when they spun a bearing.
So it's now WHAT oil you run as much as making sure it's full or more if you carve corners with the Duratec.