2001 Tahoe 5.3 high oil pressure - Chevrolet Forum - Chevy Enthusiasts Forums

2001 Tahoe 5.3 high oil pressure


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Join Date: Dec 2009
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Southern California

October 21st, 2010, 6:55 PM   #1  
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2001 Tahoe 5.3 high oil pressure

My Tahoe has been leaking oil and no one can figure out why or where. Take a look at this thread:
2001 Tahoe oil leak

Anyways, my Tahoe has always seemed to have high oil pressure. Idle when the motor is warm is 40 psi (needle straight up and down). When I accelerate from a stop the pressure goes slightly past 60. If I floor it the gauge goes to 80.

Why is it doing this? Common problem? The gauge never read erratic like I have seen in some threads.

I'm guessing the higher oil pressure is blowing out my oil filter seal and various other seals? And the truck still leaks some oil. I'm about half a quart low in 1,500 miles of driving.

 
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Bowie, MD

October 21st, 2010, 8:21 PM   #2  
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GM allows for 1 quart per 1000,which is not normal no matter what they say. You can not leak that much oil unless it is leaving puddles every time you park. If it is not soaking wet with oil under the entire engine and at least half way to the rear bumper it is not leaking all that oil it is burning it. The stock oil pressure gauge it not always accurate,you need to perform a mechanical pressure test. I doubt it has anything to do with your oil pressure.

 
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Southern California

October 21st, 2010, 10:20 PM   #3  
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MDTAHOE  GM allows for 1 quart per 1000,which is not normal no matter what they say. You can not leak that much oil unless it is leaving puddles every time you park. If it is not soaking wet with oil under the entire engine and at least half way to the rear bumper it is not leaking all that oil it is burning it. The stock oil pressure gauge it not always accurate,you need to perform a mechanical pressure test. I doubt it has anything to do with your oil pressure.
Did you see the thread I posted in the original post? While my Tahoe is probably burning some oil, I think the majority of the half quart loss in 1,500 miles is due to an oil leak under the truck. Oil drips down the filter and up by the starter.

Since I do seem to have high oil pressure, is this causing the seals to blow out?

In the mornings the motor ticks for the first 30 seconds. I don't know if this is piston slap or the valves. After the 30 seconds the motor doesn't make the noise.

I use PureONE oil filters with Mobil Clean 5000 10w-30.

 
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Bowie, MD

October 22nd, 2010, 6:59 AM   #4  
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knock on first start is normal. Yes I read the thread you posted. Drips do not equal low oil level, it would have to be a constant drip and a big puddle all the time.

 
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New York City USA

October 22nd, 2010, 9:59 PM   #5  
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High oil pressure as you describe it, running down the oil filter and so on and so forth can only be attributed to one cause and that is a blocked pressure relief valve. What kind of oil filters do you use? Typically standard quality Delcos/Fram/STPs are vented or ported in the inlet area to relieve pressure. But them cheapie Walmart, Eds Wholesome Deals made in China jobbies arent the same. They have ports in the inlet but who knows where they go.

The pressure relief valve is what you screw the oil filter into on most cars. If this is a high mile car you could have buttloads of carbon "encrudded" in that opening. Its similar to the Chrysler LH engines that had oil circulation ports in the heads that were too small for the low viscosity oil they were using and then the oil would coke up and clog the ports. And then the motor would fail from oil starvation. In your case the central orifice could be clogged so the oil has to run back to the motor from the filter through them tiny little holes which raises the pressure.

OR your oil pressure switch/sender is malfunctioning and leaking oil all over the place at the same time. Usually screwed into the block right above the filter.

Oil pumps dont tend to create EXCESS oil pressure but can create LOW oil pressure.

 
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Southern California

October 23rd, 2010, 1:00 PM   #6  
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RacerX  High oil pressure as you describe it, running down the oil filter and so on and so forth can only be attributed to one cause and that is a blocked pressure relief valve. What kind of oil filters do you use? Typically standard quality Delcos/Fram/STPs are vented or ported in the inlet area to relieve pressure. But them cheapie Walmart, Eds Wholesome Deals made in China jobbies arent the same. They have ports in the inlet but who knows where they go.

The pressure relief valve is what you screw the oil filter into on most cars. If this is a high mile car you could have buttloads of carbon "encrudded" in that opening. Its similar to the Chrysler LH engines that had oil circulation ports in the heads that were too small for the low viscosity oil they were using and then the oil would coke up and clog the ports. And then the motor would fail from oil starvation. In your case the central orifice could be clogged so the oil has to run back to the motor from the filter through them tiny little holes which raises the pressure.

OR your oil pressure switch/sender is malfunctioning and leaking oil all over the place at the same time. Usually screwed into the block right above the filter.

Oil pumps dont tend to create EXCESS oil pressure but can create LOW oil pressure.
The Tahoe does have high mileage, no doubt. The oil was changed every 3k miles or close to that. I have all the receipts since I bought the car from a family friend.

I use PureONE oil filters.

Quick question. When the car is off should the oil pressure gauge fall back to zero? Mine stops at 20. Is this normal?

 
Join Date: Jul 2010
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October 23rd, 2010, 4:56 PM   #7  
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Keith K Man, oil pressure gage should go back to 0 when the engine is not running. I have a 2001 and it goes back to 0.

Last week mine started leaking above the oil filter also, its a slight drip, that you see in the drive way now. I will have to check to see exactly were it is leaking.

In my experience with true high oil pressure, has been with the oil pump spring getting stuck and with the oil filters and by pass.

One thing you might want to try, is changing oil and use 5-30 and see if it still has the high pressure, when I have used 10-30 & 10-40 my pressure is higher, so I went back to 5-30.

 
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Bowie, MD

October 23rd, 2010, 5:48 PM   #8  
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It should go to 0 when the key if off

 
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New York City USA

October 23rd, 2010, 9:13 PM   #9  
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Hey, I m not familiar with PURE ONE, How big is the filter? I mean is it the standard 1 quart filter like you re supposed to have? If the filter is too small you may be unnecessarily creating high pressure as the oil is flowing into and out of the filter because it cannot pass through in sufficient volume. BUT>>If your dash gauge doesnt return to 0 when the car is off and you read this to determine oil pressure, the needle may be calibrated for the wrong position or broken. You ll have the manually check OP with a mechanical gauge to be sure.

 
Join Date: Dec 2009
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Southern California

October 25th, 2010, 1:04 AM   #10  
CF Beginner
Well maybe I don't have high oil pressure since my gauge shows 20 pounds with the truck off. That would make sense I guess since under high RPMs it should be around 60 and the gauge is showing 80.

What should idle pressure be?

The PureONE filters are good. Typical 1 quart filter.


Last edited by KeithKman; October 25th, 2010 at 1:07 AM.
 
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