Ok so I have a 1999 blazer zr2 4.3l 4x4 with approx. 96,000 miles on it. I just recently(last week) switched it to 5w30 full synthetic Castrol edge. I don't drive it everyday. So yesterday I get about 10 min. down the road. When I stopped at the light my oil pressure dropped to 0psi and the "check gauges" light came on. When I took off the light went off and the pressure went up to 20-30psi. Once I got home I parked it.


Started it up later in the night, the pressure went straight to 40psi and dropped to 20psi when I stopped. After about 10-15min. of driving(to the bank) went inside for 5 min. or less. Came out started it, went to 30psi and 20-30 while driving and dropped to about 5-10psi on stops.


So there's my issue. It appears to be worse during the day(when it's hot).


Any thoughts or suggestions??


Thanks guys and gals.

 

Your engine calls for 10W30. 10W has a higher viscosity (resistance to flow) than 5W. I would start there.

As your oil heats up it will thin, hence the lower pressure. Generally in these engines it starts around 40psi when cold and settles about 20psi when warmed up and idling.

Here's a good video also on oil pressure

 

Ok thanks. Just downloaded the owners manual on my phone. Didn't realize 5w30 was for colder conditions. Oops. Haha I live in FL. Ok thanks. Will try that and get back with ya.

 

Forgive me for asking the obvious...have you checked the level? Low pressure at stops usually indicates low oil. Not talking about a lower pressure at idle but when you see a huge drop down to 0-5 psi and check engine I would guess you are low.

 

haha yea my level is full