oil pressure jumping past 80 psi

[silverado98]

whem i drive it goes past 80 psi then when i im stopped at a light then goes to 35psi. i thought it could be the sending unit but not sure what do u guys think help please. ohh got a 98 c1500 with a 305

 

[SkyHighColorado]

pressure is a good thing.

 

[98_k1500]

LOL... Mine constantly stays past 80 lbs right now. High reading = open circuit. Sending unit is more than likely to blame.

 

[df2x4]

My truck has always done this. Well, not OVER 80psi but it warm idles around 30-40 and when I'm in the throttle I see around 75-80. I replaced the sending unit because I thought that was high, that actually made it read about 3-4 pounds higher. I just chalk it up to having the V6, less distance to move the oil with the same pump as the V8s.

 

[98_k1500]

Mine points straight to the right.

 

[kennythewelder]

When I had a 4.3 mine did the same thing. Then the truck I have now 5.7 L started to do it too. I had an oil leak in the intake between the head, intake, and block, in that corner where they all meet. It was on the drivers side, against the fire wall. I pulled the intake to fix the leak and I couldn't believe what I saw. The sludge build up in the oil valley where the lifters are was full of sludge. No wonder the oil pressure was jumping around, the oil couldn't get threw. After cleaning out all the sludge and putting the engine back together, I switched oil to Valvoline. This was about 4 years ago, and I haven't had the jumping oil gauge issue since. I have always changed my oil every 3000 miles. I do live in south Louisiana and it is hot here. I use to use Castor oil GTX. I have never used it again, and never will.

 

[kennythewelder]

My bad I miss read the original post. I thought we were talking about fluctuating oil pressure here, My Bad.

 

[twomanymontes]

whem i drive it goes past 80 psi then when i im stopped at a light then goes to 35psi. i thought it could be the sending unit but not sure what do u guys think help please. ohh got a 98 c1500 with a 305

Mine does too. I installed a mechanical gauge and it read pretty close to the electrical gauge. As long as the needles keeps moving up and down and never drops to 0, I'm good.