So per a recent post on the use of Pennzoil Long Life 15w 40w oil, according to Pennzoil's web page (http://www.penzoil.com/) a very informative page, BTW, they state that the Long Life oil meets not only the latest in diesel engine ratings but also in gas engine ratings, plus, it's designed to hold more particulate material in suspension than other oils. I took the plunge. The first thing I noticed is that the oil gauge reads different oil pressures than it did before, under similar circumstances. Before the gauge would not move much from the high point, but now, at idle, it reads about mid way. It still goes up to full pressure when the tach rises more than a couple of hundred rpm. The car has always used pennzoil.

Is this difference anything to be concerned about??

…tracy

Tracy,

First, are you using the same weight you were using before?

Second, oil pressure is a good indicator of worn bearings, as the bearings wear the oil pressure decreases because there is less resistance to flow. But the comparison would be made with the same oil and weight as years and miles go by.

The decreased oil pressure in and of itself by changing oil would not be anything to be worried about as long as the pressure didn't go alarmingly low. The over the road Cummins engines have their oil pressure regulated to about fifteen psi maximum. This is done to eliminate energy waste driving the oil pump. As long as there is enough pressure to cause oil flow, there is no ill effect.

Good luck,

------------------
Larry Bible
'84 Euro 240D, 516K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in
Mercedes automobiles

Thanks both of you! Interestingly, after about 2 days the oil pressure gauge has gone back to behaving as prior to the use of Long Life oil. I'm relieved, none the less at your comments!

...tracy