Oil pressure sender location

GMC guy

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#1
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MAKE: GMC
MODEL:C5500
YEAR: 2005
MILES: 280k
ENGINE
: 6.6 Turbo
DESCRIBE ISSUE....Changed oil and oil pressure went up to 80psi then drops to 40psi oil light did not come on at first, but now it is on full time. I did see an egr code at one point but it was erased. i'm sure it will be back. But what I want to know right now, is where is the oil pressure sender located? I want to test the pressure manually. I took the interior cover off and cannot see it. Thanks
 

nickb2

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#2
I am not familiar with this model. Are you sure it is a C5500. Maybe we don`t have those in canada.

I will however post a few snapshots for a 6.6l of same era model. Hope this will help.

Screenshot (104).png Screenshot (103).png
 

nickb2

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#6
Well, I really went over all my data base and still can`t find a c5500 in there.

I know they call them top kicks. Since I am a car slash light truck tech, I am only equipped with light truck models. But I am pretty sure they did not change the block model for the 6.6l dsl.

Maybe one of the other guys will chime in.

I did a research gmc_topkick_c5500_4x4_truck-exterior.png and I think I have only seen one or two up here in quebec.
 

nickb2

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#7
But if you confirm it is a VIN number 2, those specs I gave should be good and location the same.

40 psi is normal at 1800rpm, but 80!!:eek:

Good call to check manually. If on your oil pressure tester which you know is good, and oil pressure specs are in the zone, install an auto meter oil pressure gauge afterwards to avoid expense. I have always had success with auto meter gauges. I think I still have stickers on my tool chest. Yup, just checked, they are still there. My toolbox is way old and way to many stickers from the stuff I have installed.:D

They are a great company. I like them better than the equus or the sun models.
41GDK7TKPSL.jpg

Unless the client is cheap and needs a manual gauge, this what I always recommend. But they are expensive. But for a truck of this price and torque. Worth the expense.
 
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GMC guy

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#8
okay, 70 at start, then drops to 35 at idle. then is around 40 driving. I have 3 egr codes. Could this be the cause of the high oil pressure?
 

billr

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#9
EGR operation should have no effect on oil pressure.

Edit: I gotta ask... reading this thread I got the impression this is a diesel engine, and don't think of diesels having EGR. Where am I going off in the weeds?
 

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#12
This is a diesel yes. That is strange yes. The scanner i use has 3 egr codes when i connected it. but ok, i got this oil pressure reading right after an oil change. i took a chance and drove it around yesterday. It performed well. Oil pressure was at around 35 and a little upward when accelerating. Oil light still on.
 

nickb2

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#13
This is a diesel yes. That is strange yes. The scanner i use has 3 egr codes when i connected it. but ok, i got this oil pressure reading right after an oil change. i took a chance and drove it around yesterday. It performed well. Oil pressure was at around 35 and a little upward when accelerating. Oil light still on.
So now you have to check why it is coding EGR codes. Can you post codes and I will supply flowcharts for that.:beer::bat:
 
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nickb2

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#14
If you have correct oil pressure readings, go for a auto meter. Cuz the way I see this going, it is electrical or the sender is not reading right. A IPC is very expensive for these top kicks. Cheaper and more reliable to install a manual gauge and ignore the oil pressure light.

For the egr codes, post them. We will help further after that.:):bat: