Low Oil Pressure

[LeRoy]

I took my new (to me) 2005 Silverado 2500 on a road trip pulling the camper, which is about 7500lbs.

Before the trip I had the local garage double check and all the fluids were looking good and at the proper level. When stopping to get fuel I also checked everything.

When driving the oil pressure just seems to be way too low, or at least way lower than i expected. Its always about 1/2 way between 0 and 60. When I had to sit at idle in bad traffic, it dropped lower and lower and lower until it seemed to near the red line. When the RPMs were up it went up slightly, but still never up to 60.

However, whenever I'd stop and check the oil it was above the top bar.

I seem to remember it being nearer to 60 when I was driving around town before we left not towing, but of course can't remember exactly. Now when we're home and driving around, not towing it still is around 30.

Is it normal to see my oil gauge so low? Is this a common problem?

My one thought is that perhaps the dealer put a 10w30 oil in, which is "OK" according to the manual.

 

[Slammed2007Lbz]

There was a problem with low oil pressure but i think it was in the LB7 trucks i can't recall. If they put 10-30 in it that would definitely lower the pressure compared to 15-40. A lot of these trucks only have like 28psi at idle iirc. My truck idles at 30psi and usually at 60psi while driving iirc.

 

[super diesel]

This is dependent on oil temp too. The hotter the oil, the lower the pressure. Let us know what truck you have and any info on it. With the LLY here, it runs the oil just as hot as my LB7. Are you climbing any hills with it (grade pulling)?

 

[LeRoy]

I have a 2005, so I believe that makes it an LLY.

When I noticed that it was low, I was near Atlanta on I75. While its not flat its far from steep grades.

I live in Florida, near the coast, so around town driving is perfectly flat and always around 30psi.

 

[Slammed2007Lbz]

Superdiesel will tell you anything you want to know about oil temps and psi etc.. he is very knowledgeable in that area:thumb:

 

[Kartmnn]

I tow with my 06 lbz for a living. The pressure towing is always around 30-35 at highway speed or around 1700rpms. At idle its less then 30. Truck holds better pressure empty because the temps are down as its not working as hard. Truck has 142,000 on it and as been working great so far for me.

 

[super diesel]

Superdiesel will tell you anything you want to know about oil temps and psi etc.. he is very knowledgeable in that area:thumb:

Jees man! Thanks much, but I wish I was far smarter in this area. Could have saved a few more motors by now.

To the OP. If you feel you are getting low oil pressure, I would install a quality oil temp gauge to make sure it's running at the temps the oil should be. If it gets to hot, this will cause the oil and the additives to break down for good (or at least till you change the oil), and the oil will always run lower pressure after this has happens. It did in my case and I firmly believe it caused a spun main bearing in a motor I had. This was costly. It only takes once of over temping it. If it's running high, I would recommend one of 2 things (or both as I do). A good quality synthetic (I've been experimenting with Schaeffer 9000 5W-40 and I'm happy with it and will afford a safety margin more than the regular dino based oil will) or a good oil cooler (problem is this is a build it yourself thing at the moment beside a few parts I do for the set up). For the long run and anyone hauling heavy loads, I firmly recommend the oil cooler. Read the thread "Oil cooling" when you have a little time if your concerned about this. It tells you most every thing you need to know and it's kept pretty up to date with testing and such.