PENZOIL Platinum HM lower oil pressure

[Rattler]

Hi all. I have a 97 ram 1500 with a 3.9 magnum. It has 110,000 on the clock. I normally use Mobile 1 EP 5w30 but the price with rebate was too good to pass up on the Penzoil Platinum High Mileage 5w30.

I've only got 14 miles on the oil but have noticed significantly less pressure with the PP at idle. Anyone have an idea what is going on?

 

[atikovi]

The old filter was loaded with dirt causing a restriction and resulting in higher pressure. New filter, less restriction, lower pressure.

 

[zfasts03]

My 1997 Ram 1500 4x4, 5.9 also has lower oil pressure with some oils. I think Pennzoil is slightly lighter of an oil at operating temps.

As long as the oil pressure doesn't get below about 1/4 on the gauge at idle you should be good. Mine still comes to a little over 1/2 when cold and higher RPM's. Also it is hotter out so the oil is running hotter and thinner.

The oil pressure sender is after the filter, so I don't think a new filter would cause lower pressure. The way I understand your old restricted filter would cause lower pressure readings not a new filter.

 

[Rattler]

Alright, thank you guys. I'm not going to worry about it then. Zfasts03 that's exactly how my dash pressure gauge is behaving. I'm glad I asked before chasing a problem that wasn't there with a new sending unit and high volume oil pump!

 

[OilUzer]

When the light comes on something is wrong.

My oil pressure gauge has no marking on it ... No numbers, no color (red, good, bad, ok) ...
It's usually somewhere near the middle. It's a boring garage and I ignore it most of the time.
I think they wired the oil light to it. If the light is on, the gauge may go all the way up or down.
If light is off, stays in the middle.

Old cars or most new cars have no oil pressure gauge.
I prefer a digital readout. Analog gauges with no numbers or scale are meaningless!

 

[Mad_Hatter]

PP HiMi has a VI of 170 so it shouldn't be thinning that much at operating temp, if at all. (higher the # the less susceptible to the effects of high operating temperature?) And it has a 10.1kv @100c so it's a middle of the road Xw30, right?

Can you get a low oil pressure light with these numbers and it not be something else causing it??

 

[littleant]

2002 Jeep 4.0 162,000 miles Have the same results with Pennzoil Platinum High Mileage 5w30 and 10-30. About 20 psi at idle where as the same conventional oil presure is 30 psi at idle. But I will not worry about it because this winter at -30 to -40 with fram ultra filter the Pennzoil flows great far superior at cold temps then the conventional.

 

[Rattler]

My oil light isn't kicking on. The pressure gauge reads the 1/4 Mark at idle once warm at idle and 40 or a bit over while driving. Mobil 1 the needle barely moved.

 

[demarpaint]

Originally Posted by Rattler
My oil light isn't kicking on. The pressure gauge reads the 1/4 Mark at idle once warm at idle and 40 or a bit over while driving. Mobil 1 the needle barely moved.

I would confirm actual oil pressure with a mechanical oil pressure gauge and eliminate any guess work. Dash oil pressure gauges are for the most part a glorified idiot light and don't tell much of anything in cases like this.

 

[Triple_Se7en]

I agree withe Demar. If you are changing oil brands ...aka... formulations - changing viscosities, your oil gauge will show changes also. Gauges also change with our four seasons here in Michigan.
Best way to judge a factory oil gauge reading is thru consistency. Keep things the same with your oils and document how differing, drastic weather changes your readings. Then compare year-to-year.
Most owner manuals sitting in your glovebox has several pages on the back for taking notes. Most have never written a thing on those pages.

 

[Rattler]

I'll hook up a real mechanical pressure gauge. I know exactly what to expect from Mobil 1 on the gauge by the season, the pphm is a big change that is unexpected though in the way the gauge is acting.