Strange Oil pressure gauge

[M123]

Hi.
My oil pressure gauge are a bit funny, now I have kpa on my 02.
As I understand the guage are filled with some oil, the strange part are it can walk the scale when my truck are of without any electronic on. My guage read 0-500 kpa. With the truck running on idle it read approx 415 and that are 59 psi so the pressure are okay. But off it can walk up to 137 that's 1/4 of the scale and sometimes it can stay on 275 when I kill the engine, but when I turn on and off the key it do drop down to 0.

Anyway do someone know what oil they are using in them and how do I fill it up again?
Note it's a 02 and not the stepmotor construction that did come 03.

Sorry if I explain myself bad.

Thanks.

 

[M123]

Did find this video but honestly I don't know what damper oil are?

 

[PNWYukon]

If it is moving around on its own, there is an electrical problem somewhere or:

“P” 95-02 Oil Pressure Gauge Air Core Stepper Motor For GM Truck/SUV Clusters​

The original yellow motors use regular dampening oil which dries up from age, these white motors use silicone dampening oil that won’t dry up like the yellow motors. We have repaired thousands of clusters using these these motors.

"P" 95-02 Oil Pressure Gauge Air Core Stepper Motor For GM Truck/SUV Clusters - US Dashworks

For your consideration we are offering used, reconditioned replacement “P” motors, these are a direct replacement for the original yellow colored motors in your cluster now. The “letter code” determines which gauge the motor will replace, the color of the plastic doesn’t make any difference...

usdashworks.com

 

[M123]

If it is moving around on its own, there is an electrical problem somewhere or:

“P” 95-02 Oil Pressure Gauge Air Core Stepper Motor For GM Truck/SUV Clusters​

The original yellow motors use regular dampening oil which dries up from age, these white motors use silicone dampening oil that won’t dry up like the yellow motors. We have repaired thousands of clusters using these these motors.

"P" 95-02 Oil Pressure Gauge Air Core Stepper Motor For GM Truck/SUV Clusters - US Dashworks

For your consideration we are offering used, reconditioned replacement “P” motors, these are a direct replacement for the original yellow colored motors in your cluster now. The “letter code” determines which gauge the motor will replace, the color of the plastic doesn’t make any difference...

usdashworks.com

Thanks, this did clear some questions. I was also thinking the same first about the electrical, but in that order the cluster must be hot all the time and ground leaking in to the guage?
Now I haven't any wiring diagram so I can follow that up.

My second guess was air in the motor that force it to stay and walk, but in the same time the magnet in the motor should prevent that and hold it in to place.