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Posted

I wish I had seen this a few months ago. Had this very same issue while driving home to DE from NYC. Oil pressure took a nose dive and I was still 60+ miles from home on the NJ turnpike. Very high pucker factor!

 

Question, is this something that happens frequently? How often should the screen be replaced?

Posted

Seems to still be confusion here on issues with these trucks regarding the oil pressure sending unit screen. 

 

First and foremost let's clarify which engines have the screen below the oil pressure sending unit.  In short it's only on engines equipped with active fuel management.  In the full size trucks that equates to any 5.3 in a GMT900 bodied truck from 2007 through 2013(LY5, LH6, LC9 etc).  Otherwise it would also be present in the L76 6 liter trucks as well as the L94 equipped 6.2 powered SUV's and the oddball hybrids 6 liter (LFA or LZ1).

 

  Regular L92 or L9H 6.2's, the LY2 or L20 4.8 or the LY6 and L96 in the HD trucks do NOT have the screen under the sensor.

 

Furthermore no GMT800 truck (1999 through 2007 classic) has the screen as those are Gen 3 engines and this pressure sender screen is a Gen IV thing only as outlined above.

 

 

  • Like 1
Posted

I have the same issues but I pulled my sending unit and the screen was fine. It looks like I have leaky valve seals. I burn quite a bit of oil. Especially in colder weather when the metals seem to shrink a bit. 

Posted
On 3/5/2019 at 9:42 AM, jfath14 said:

I have the same issues but I pulled my sending unit and the screen was fine. It looks like I have leaky valve seals. I burn quite a bit of oil. Especially in colder weather when the metals seem to shrink a bit. 

Just because the screen looks fine doesn't mean the trash didn't sink back down. Check out my video and see how to fix it for good.

 

 

  • Like 1
  • 1 month later...
Posted (edited)

Can anyone tell me if there is some kind of fail safe for low oil pressure on a 1999. GMC Sierra 5.3?? I was driving on the interstate when it cut off on me and I couldn’t get it started back up. Wouldn’t even attempt to turn over. I know there was plenty of oil in it(just added and checked before I got on the road). Right before it died my oil pressure dropped to 0 and my DID said low oil pressure. TIA

Edited by 99GMCZ
Misspelled
  • 2 months later...
Posted

Seems like most relavent place to ask this.

I have an 07 classic that the oil pressure gauge is always pegged at 80 psi until you floor it, then it goes to 0 and get a warning chime. Let off the gas, pressure goes back to 80 psi.  I replaced the stepper motor in the cluster and it had no effect.

I also have an 05 yukon denali that does the exact same thing , low oil pressure warning chimes all the time when driving. Oil sending unit on this one was changed about a year ago, but not the stepper.

 

Any ideas? Thanks

 

Posted
On 6/26/2019 at 7:02 PM, Jim1977 said:

Seems like most relavent place to ask this.

I have an 07 classic that the oil pressure gauge is always pegged at 80 psi until you floor it, then it goes to 0 and get a warning chime. Let off the gas, pressure goes back to 80 psi.  I replaced the stepper motor in the cluster and it had no effect.

I also have an 05 yukon denali that does the exact same thing , low oil pressure warning chimes all the time when driving. Oil sending unit on this one was changed about a year ago, but not the stepper.

 

Any ideas? Thanks

 

More than likely it is just the oil pressure sensor. You don't have the filter under the sensor on the old body style but the sensor is in the same place and the replacement is the same minus the filter. Look at the video above. Still blow the passage out to make sure nothing is clogging it. 

 

On 3/6/2019 at 5:59 PM, carnau said:

 

 

 

 

Posted

Seems like most relavent place to ask this.

I have an 07 classic that the oil pressure gauge is always pegged at 80 psi until you floor it, then it goes to 0 and get a warning chime. Let off the gas, pressure goes back to 80 psi.  I replaced the stepper motor in the cluster and it had no effect.

I also have an 05 yukon denali that does the exact same thing , low oil pressure warning chimes all the time when driving. Oil sending unit on this one was changed about a year ago, but not the stepper.

 

Any ideas? Thanks

 

Posted

I guess maybe the denali could have gotten a faulty new sensor. Or wasn't cleaned out enough.

Going to follow video advice, and blow out the tube .

 

  • 1 month later...
Posted

Soooo, the oil pressure isn’t low, the sending unit is just not seeing full pressure because of the screen? Can you just remove it with a pick or something and pop in the new screen or is it more involved then that? If so I’m gonna order a screen and swap it out in like 15 min. 

Posted
On 8/9/2019 at 12:52 AM, Farley_shawz said:

Soooo, the oil pressure isn’t low, the sending unit is just not seeing full pressure because of the screen? Can you just remove it with a pick or something and pop in the new screen or is it more involved then that? If so I’m gonna order a screen and swap it out in like 15 min. 

Watch my video above.

  • 1 month later...
  • 4 weeks later...
Posted (edited)

Carnau, watched the video you posted, thank, might come in handy in the future.  Just kinda crappy you have to keep this whole thing in the back of your mind in case this problem pops up when you're on the road somewhere.

Have you done the job?  Someone earlier in this thread mentioned using a regular deep socket but the guy in the video says you need a special one?   I'd think a regular 6 point socket would work..?

Edited by Fisherguy58
Posted (edited)
On 3/6/2019 at 5:59 PM, carnau said:

Just because the screen looks fine doesn't mean the trash didn't sink back down. Check out my video and see how to fix it for good.

 

 

much thanks for that video !! had 20psi hot idle now 38

Edited by nqabigt
spelling
  • 1 month later...

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