Oil Gauge Pegged at 80... Sending Unit?

[Dantheman-2003]

My oil gage has been pegged for sometime now (Pegs out without engine running). 5.3 LS runs and strong, no issues. Wondering if anyone had success changing their sending unit? What is the socket size for the unit? Sucker looks like it's back in there pretty good.

Let me know- thanks!

Dan

 

[StephenPT]

Yeah - it's buried back there. This is a pretty decent video that shows how to get at it without taking off the upper intake.

 

[Dantheman-2003]

Yeah - it's buried back there. This is a pretty decent video that shows how to get at it without taking off the upper intake.

I saw this video. Mine is an 05- so I think it's in a little different location (more accessible hopefully)

 

[swathdiver]

I like the idea of just pulling the intake to get at it. Takes a few minutes longer, no broken back or cut up fingers/hands.

 

[Fless]

Lisle 13250 is the one. I changed one for my neighbor using it and not pulling the intake. A lot of that is by feel, but more do-able if you don't have gorilla mitts. Yours may not have that shield (that's in the way) shown in the video.

 

[rockola1971]

If the wire become disconnected, cut in half or the Oil Pressure sending unit becomes bad the symptom is your oil pressure gauge will peg itself to far right. Also it is quite possible the stepper motor in the cluster is bad as well. Does the needle go far left when engine shutoff and then peg itself far right when engine started?

 

[Fless]

If the wire become disconnected, cut in half or the Oil Pressure sending unit becomes bad the symptom is your oil pressure gauge will peg itself to far right. Also it is quite possible the stepper motor in the cluster is bad as well. Does the needle go far left when engine shutoff and then peg itself far right when engine started?

^^^ This. Determine if the the gauge is working properly first, then move on to the oil pressure sender circuit and the sender.

 

[OR VietVet]

Exactly what @rockola1971 and @Fless said. Anyone can muddle thru the hassle of replacing the sensor and accomplish it or not and wish they had not even tried. But, basics first and determine if the sensor is actually bad. I would bet, over 10% of my posts on here speak of "basics first". I have told members to throw parts at a problem before but that was when it was clear in the post that they were 3/4 of the way there already. I love spending other people's money, any day.

By the way, I love "wobble extensions" when under the hood and rig. I also see the need for my trusty 1/4" drive battery powered ratchet.

 

[Fless]

To add to that, a flex head ratchet, especially for this job. Makes it easier but it's not impossible without it.

 

[OR VietVet]

I am thinking a shorter flex handle would have been easier to use in this video.

 

[Dantheman-2003]

If the wire become disconnected, cut in half or the Oil Pressure sending unit becomes bad the symptom is your oil pressure gauge will peg itself to far right. Also it is quite possible the stepper motor in the cluster is bad as well. Does the needle go far left when engine shutoff and then peg itself far right when engine started?

Yes- needle pegs when engine is off. I replaced the dash cluster because I had a bunch on lights out. Still pegged. Likely the sensor so here we go. Wish me luck!

 

[WestLinnYukon]

I just swapped mine out using a wobbly and two extensions. It took 10 minutes start to finish. I put a rubber mat in the compartment and laid on it so I was looking over it. It wasn’t easy, but it wasn’t as hard as I thought it would be. Actually I spent more time worrying and watching videos than replacing the thing… also mine was pegged at 80 with key on - even no start.

 

[MassHoe04]

Be careful any time you are trying to lay across the engine compartment...

I was doing that when the plastic "T" connector that goes to the heater core had to be replaced.
It never occurred to me, that the purge valve and other things sit under the pretty Vortec engine cover.
When it came time to replace the purge valve, I saw where it was and realized... Dang! I am glad I didn't snap that thing off when I was sprawled across the top of the engine working on the heater fitting!

I made a mental note to be more careful when trying to reach things at the back or deep down below.

 

[WestLinnYukon]

Be careful any time you are trying to lay across the engine compartment...

I was doing that when the plastic "T" connector that goes to the heater core had to be replaced.
It never occurred to me, that the purge valve and other things sit under the pretty Vortec engine cover.
When it came time to replace the purge valve, I saw where it was and realized... Dang! I am glad I didn't snap that thing off when I was sprawled across the top of the engine working on the heater fitting!

I made a mental note to be more careful when trying to reach things at the back or deep down below.

Great feedback! I lucked out and didn't break anything, but I have a brush guard that took some of my weight. I also took the cover off. Mostly my weight was on the front subframe. But great call that people should use caution when laying on the engine compartment. Lots going on in there.

 

[Dantheman-2003]

Be careful any time you are trying to lay across the engine compartment...

I was doing that when the plastic "T" connector that goes to the heater core had to be replaced.
It never occurred to me, that the purge valve and other things sit under the pretty Vortec engine cover.
When it came time to replace the purge valve, I saw where it was and realized... Dang! I am glad I didn't snap that thing off when I was sprawled across the top of the engine working on the heater fitting!

I made a mental note to be more careful when trying to reach things at the back or deep down below.

 

[Dantheman-2003]

Update 11/13/22: successfully changed the sending unit. Ratchet, socket and a few extensions. Seemed to fix the problem temporarily. Oil gauge pressurized to 40. Then took her for a trip to Reno this weekend and it’s pegged again at 80, same as before. I used an AC Delco part. I will check the wiring plug tomorrow to see if it came loose or something. Otherwise bad part?

 

[Dantheman-2003]

Great feedback! I lucked out and didn't break anything, but I have a brush guard that took some of my weight. I also took the cover off. Mostly my weight was on the front subframe. But great call that people should use caution when laying on the engine compartment. Lots going on in there.

I should have read this beforehand. While changing my sending unit was successful, upon starting the engine choked out and died. Turns out My fat ass knocked loose the air tube.