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8.1 Oil Pressure Numbers, What You Got?

10.90 hot rod

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10.90 hot rod Enthusiast

10.90 hot rod

Posted
Posted

Just a quick poll if I could. What kind of oil pressure numbers do you have? I found one other thread but not alot of info. there. I have around half or a tick below hot going down the road and a tick below one quarter at idle. I use 5W30 mobile oil. Everyone knows that GM says that 8 psi is okay hot at idle for this engine , but that doesn't give me alot of confidence. Also, anyone have any ticking sounds on cold start up. I know the 6 liter has it's demons that way, but I was wondering if anyone else had a 8.1 that ticked for about 40 seconds on cold start. Thanks

dewfpo Senior Enthusiast

dewfpo

Posted
Posted
Just a quick poll if I could. What kind of oil pressure numbers do you have? I found one other thread but not alot of info. there. I have around half or a tick below hot going down the road and a tick below one quarter at idle. I use 5W30 mobile oil. Everyone knows that GM says that 8 psi is okay hot at idle for this engine , but that doesn't give me alot of confidence. Also, anyone have any ticking sounds on cold start up. I know the 6 liter has it's demons that way, but I was wondering if anyone else had a 8.1 that ticked for about 40 seconds on cold start. Thanks

 

At hot idle I have ~25 psi, going down the road ~45 psi max hot. I run 5W40 synthetic.

 

DEWFPO

spackelman Enthusiast

spackelman

Posted
Posted
Just a quick poll if I could. What kind of oil pressure numbers do you have? I found one other thread but not alot of info. there. I have around half or a tick below hot going down the road and a tick below one quarter at idle. I use 5W30 mobile oil. Everyone knows that GM says that 8 psi is okay hot at idle for this engine , but that doesn't give me alot of confidence. Also, anyone have any ticking sounds on cold start up. I know the 6 liter has it's demons that way, but I was wondering if anyone else had a 8.1 that ticked for about 40 seconds on cold start. Thanks

 

At hot idle I have ~25 psi, going down the road ~45 psi max hot. I run 5W40 synthetic.

 

DEWFPO

 

 

 

Cold start is about 60 psi. Hot idle is about 25 psi. Crusin about 50mph is about 60 psi

 

I only use use mobile 1 10-30w (since new).

michigansilver03 Enthusiast

michigansilver03

Posted
Posted

That's the 8.1 letting you know it's cold. Actually it's called piston slap and it's does sound like a diesel for the first minute or so. My oil pressure is about the same so the rest of you folks any where from 60 to 25.

testdrive Enthusiast

testdrive

Posted
Posted

just about the same, not changed from when it was new

 

At hot idle I have ~25 psi, going down the road ~45 psi max hot. I run 5W40 synthetic.

Ryno Enthusiast

Ryno

Posted
Posted

02' 85k miles. I run rotella 15w-40. Cold start, 60+. Warm 35-40 idle, still 60 when rpms come up. It goes down about 5 psi in the summer (100+ here for 3 months).

10.90 hot rod Enthusiast

10.90 hot rod

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Posted

Thanks for all your replies. Just a quick follow up. I don't drive my truck much in the winter to save it from all the Ontario salt, so I decided to take the time and look inside the motor. Even though it is a 4x4 I had the oil pump in my hand in 2 hours. I really didn't find anything wrong at all. The pump had minor wear and the motor is extremely clean inside. For the cost of the $75 dollar oil pump ( melling M307-307) I put it in anyway. I also changed my oil to Castrol Syntec 5W40. The truck went up in pressure, Hot pressure : 55 at cruise and 25 at idle. My slight lfter tick and piston skirt noise still last 30 -45 seconds cold, but is quiet as a Church mouse hot. Some could say the viscosity change ( from 5W30 Syntec) is solely responsible for the pressure increase, but the truck never had that high of cruise pressure ever. It was a Saturdays worth of work but gave a big piece of mind .

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