Oil filter pressure release valve/Low oil pressure light

[GossamerH2]

HELP !!! My 07 H3 has been having problems with low oil pressure at idle. It started about 1 1/2 years ago after having the radiator replaced. A month later I had the thermostat replaced because it seemed to be running hotter than it used to plus the low pressure light started coming on which the Dealer said was because the engine was filled with sludge and he suggested I put a 1/2 Qt. of trans. fluid in it and run it for 100 mi. then change the oil. So I did but the oil light started coming back on 3 month's later. At first it only came on intermittently, it would go 3 to 4 months without it coming on then it would come on several times then stop but lately it's been coming on after it gets hot when idling. Also the last couple days here in NJ. it's been above 90 and the truck got really hot while sitting in traffic (a little above the 3/4 line on the temp gauge) I bought the H3 new in 2007 and have changed the oil every 3 to 4 months since I've owned it so I can't understand how it could've had a sludge buildup. I've changed the oil 7 times since it started each time either flushing it with motor medic first or the 1/2 Qt. of trans. fluid and drive it 100 mi. and I've also replaced the oil sensor sending unit as well as the cam shaft positioning solenoid but no luck it's still coming on. I read a thread on here the other day about the oil filter pressure release valve so I picked 1 up from the dealer and got 6 Qt's of 5w30 oil but I have no idea how to change the valve or where it's located. Has anyone else had this problem and changed the pressure release valve and if so A.) Where is it located and how hard was it to change B.) Did it help ? The H3 currently has a little over 115,000 on it and I just started a new job that requires putting a ton of miles on the truck so I need to figure this out and get it fixed soon ! Thanks,

 

[woodwardsh3]

With to days oils I dont think your motor is sledged up. IV taken many old motors that were not taken care of and they had minimal sludge build up in them.

 

[alrock]

Haven't done the valve, just the switch above the filter.

 

[alrock]

If it is getting that hot while sitting still, I would verify of the fan clutch is working properly.

Are you getting trouble codes?

 

[Reloader]

Oil pressure bypass valve is probably on the actual oil pump assembly which is on the inside of the front timing cover I believe.
Have you tested actual oil pressure with a mechanical gauge at the oil pressure sensor port? Did you replace oil pressure sensor with a genuine GM one or aftermarket one? I have found that cheap aftermarket parts can be problematic. Oil pressure sensors should always be replaced with oe ones.
Could be that oil pump itself in worn and not producing adequate oil pressure when hot. Try thicker oil and see what happens.

 

[SedonaBound]

Maybe this diagram will be helpful. Are you sure you don't have a bad head bleeding coolant into the oil and sludging it up? Its almost impossible for decent oil to build up serious sludge these days without help.

PS Find a different shop. Trans fluid in the engine is folk medicine for cars.
http://www.wholesalegmpartsonline.c...y_driveline=0&ukey_trimlevel=0&modelYear=2006

 

[Best4x4]

I'd change out the 20.00 oil pressure switch before jumping to any conclusions. My 07 H3 I had with 76K on it when I got it had the darn low oil pressure warning go off after I changed the oil.... Before I jumped to any conclusions I bought a new oil pressure switch, and upon removal of my original unit I discovered it had failed internally and the electrical connector was full of oil. Slapped in the new one and I never had another low oil pressure warning.

Also if you changed your thermostat from the OEM unit that was originally in your H3 then yes your engine temps are going to go up as the thermostats although sold as 180F units are actually 190F units (GM Changed the temp due to emission reasons). When I changed out my 07's thermostat it went up, but I never got past 216F in the summer time. Before that with the OEM unit it was like 206F.

 

[Can007]

Any updates?