High oil pressure
 

On my 2005 GMC Z71, the oil pressure gauge is registering 80 psi at all times even when I just turn the key on. Any ideas???

side bar: Why does the majority or the users on here feel the need to denote whether or not their truck has the z71 package?

So your 2005 GMC "Z71" with an ambigious engine has an oil pressure problem?
Relevant information would be helpful unless you have the 1 truck in the world that runs oil to their skid plate and shocks... If that is the case then check your flux capacitor for possible issues...

Ok, ok, ok...

Sounds like there is a restriction somewhere...

I hate to say this but you might need to flush that thing out (flushing can cause more harm than good in some instances). Since you already have a problem. I would do the following:

1. Change oil and filter (go cheap on the oil because you will most likely have to drain it again very soon...), if that fixes it then thats that, if not....

2. Flush your engine.. either with karoseen or berrymans or sea foam, whatever... you might have to do this more than once... do not put any load on your engine while that crap in in your oil.. Just let it idle...

Drain, new filter, new oil. check to see if the problem is fixed.

If the problem is fixed drive the truck for a few days and change the oil and filter again to make sure that none of that flush crap is still in there..

3. Ensure the pressure reliefe valve is working on(in/around?) your oil pump. maybe replace pump if deemed necessary..

4. Drive it till it blows the filter off.. replace filter and spent oil and continue till it happens again..

Good luck...

Dont waste your time hunting for a restriction....You have a bad pressure sensor or a shorted wire to the sensor.......

yep if it reads 80 all day, even with the key on truck off... bad sensor. its not fun to get to.. or it wasn't on my 02 anyway

My bad, next time I'll say 2005 GMC Sierra Crew Cab 1500 Z71 5.3L V8. Maybe thats more relevant. Thanks for the help.