Oil pressure LOW at high temps
#22
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We never run anything under a 40 weight oil in out built motors.Ussually a 10w/40. The 30 weight is just too thin and when oil temp gets high it can break down.
What your seeing with the low pressure when hot is the oil temp getting high.I've seen Vette's running 190 coolant temps but the oil is hitting 250 degree's on the hot days.Some hit 280-290 after some good runs.
I'd switch to some thicker oil and see how it does.
What your seeing with the low pressure when hot is the oil temp getting high.I've seen Vette's running 190 coolant temps but the oil is hitting 250 degree's on the hot days.Some hit 280-290 after some good runs.
I'd switch to some thicker oil and see how it does.
#23
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I've been wondering too. I've it similar and have that high pitch too BUT I thought its an idle pulley bearing. I've got M1 10 40. I want it thicker. I will say I was SUPER carefull when I put in the tube. I even modded the Windtray to have the tube in the stock location. Thing is I'm going to do a cam swap and will replace the pump jus in case. I do have a new LS6 pump.
I am worried, I've got maybe 300 miles on it.
60 psi cold
40-45 2k hot
35-38 idle hot
Not happy with it, my LT1 is better than this.
I am worried, I've got maybe 300 miles on it.
60 psi cold
40-45 2k hot
35-38 idle hot
Not happy with it, my LT1 is better than this.
#25
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I'm new to the LS1 family of engines but I know one thing for sure 30 to 40PSI of hot oil pressure is perfect. Even 25PSI hot is good. Most of you are use to the stock .0008 - .0015 bearing clearances that gives those high oil presure readings and allows you to run that thin 0w 30 oil. However, when the clearances are opened up to say .002 - .0025 your hot idle presure will drop some and you most-likely will need to run a heavier oil; something like 10-40 or maybe even 20w 50.
#26
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I only run 10w-40 Synthetic oil in my LS motors. These are high performance engines that need oil that can stand up to stress better. Synthetics also flow better in cold weather. Try it for awhile and see how it performs. If you are still having pressure problems after running the synthetic, then check your pump and/or O-Ring for problems.
#27
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So nice to hear someone else say this. I've been running 20w50 in my 427ci for 6+ years and its friggin great. Engine loves it. Pressures are great. 124,000 miles.
People think I'm crazy for running such thick oil. They just don't get it.
On very hot days the oil definitely gets thin and the pressures drop down, but on the gas its always jacked up to around 40psi crusing steady.
.
People think I'm crazy for running such thick oil. They just don't get it.
On very hot days the oil definitely gets thin and the pressures drop down, but on the gas its always jacked up to around 40psi crusing steady.
.
#28
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You say "when really hot".....45psi isn't bad at 5,000rpm. If your psi didn't climb at all from whatever it is at idle, then you'd have some trouble.
There's absolutely nothing wrong with trying 20w50...thats what I use. Been using it in my 427ci for 6+ years, its perfect.
Give it a try.
.
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im sory, but a 20psi idle is not normal on any ls motor. My stock 100k motor idled at 35psi hot, heads and cam.
Bought a 427, cold idle was 50, hot idle was 20, ended up needing barings, had to rebuild it.
The most important question to ask yourself is if the oil pressure has stayed the same thoughout the life of the motor, or if it's fluctuated.
if your **** has always banged 20psi hot from day 1, then you're probably ok, i say thats stupid low, but if it's working then whatever.
If it used to be 35-40 hot idle and now its 20hot idle, i'd venture to say you're due for a rebuild Ive never seen any built stroker ls6 pumped get 20psi hot idle. ever.
Bought a 427, cold idle was 50, hot idle was 20, ended up needing barings, had to rebuild it.
The most important question to ask yourself is if the oil pressure has stayed the same thoughout the life of the motor, or if it's fluctuated.
if your **** has always banged 20psi hot from day 1, then you're probably ok, i say thats stupid low, but if it's working then whatever.
If it used to be 35-40 hot idle and now its 20hot idle, i'd venture to say you're due for a rebuild Ive never seen any built stroker ls6 pumped get 20psi hot idle. ever.
#30
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Also agree on the 20 psi at idle being terrible. I just had a buddy go through this **** were his oil was that at idle. He spun two main bearings. With my 5.3 150k miles on it still never got under 40psi and im in central texas. Now with my ls1 stock pump and about 15k miles I still never get under 40 psi even when the truck is hot as hell and passed the 210 mark on the temp gauge. And at around 3000 rmps my oil pressure is around 80 psi. Somethin is wrong and the sooner you realize it and stop driving it the less damage you will do. It is not that hard to check out the o ring or change the pump out. Even with a stock pump you got kickin around somewere to see what the pressure does. And I run snytec 10w30 with these pressures in 100+ degrees days and after wot.
#31
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I agree that if a motor starts its life making 40+psi oil pressure hot and down the road it starts making less then yes, something is wrong. But most built motors have wider clearances and often have less pressure. My old BBChevy had 18psi hot oil pressure and stayed that way for years with no problem.
#32
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Well, the guages in our cars aren't the greatest anyway.
You say "when really hot".....45psi isn't bad at 5,000rpm. If your psi didn't climb at all from whatever it is at idle, then you'd have some trouble.
There's absolutely nothing wrong with trying 20w50...thats what I use. Been using it in my 427ci for 6+ years, its perfect.
Give it a try.
.
You say "when really hot".....45psi isn't bad at 5,000rpm. If your psi didn't climb at all from whatever it is at idle, then you'd have some trouble.
There's absolutely nothing wrong with trying 20w50...thats what I use. Been using it in my 427ci for 6+ years, its perfect.
Give it a try.
.
Ive been meaning to reply to a few other people out there, but I dont have a lot of time right now..
But to replay back to you.. Id wanna say, It did climb from abou 22psi to 45psi...
So I guess it is ok... I guess its just hot and Im putting a lot of load on the engine..
But I want really paying attention, but I was looking the other day from the corner of my eye and, it does "seem" to stay at about 45psi from 3500 til 5500.. and it didnt seem like it climbed up gradually.. so I just am kind of worried for that also,.. and I will make sure of this, soon, when I get a chance....
but if a lot of people are saying 22psi or so is fine , after the oil gets hot, then, Im not troubled too much anymore..
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update:
The oil pressure gauge was fluctuating a bit today..
When it was at 22-25 psi and I went WOT, it climbed to about 40psi, but seemed to quickly go back to 35psi then again quickly back to 40-45psi....
Also, as I mentioned before, some oil is getting consumed. I was the low oil light come on later on today..
The oil pressure gauge was fluctuating a bit today..
When it was at 22-25 psi and I went WOT, it climbed to about 40psi, but seemed to quickly go back to 35psi then again quickly back to 40-45psi....
Also, as I mentioned before, some oil is getting consumed. I was the low oil light come on later on today..
#34
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update:
The oil pressure gauge was fluctuating a bit today..
When it was at 22-25 psi and I went WOT, it climbed to about 40psi, but seemed to quickly go back to 35psi then again quickly back to 40-45psi....
Also, as I mentioned before, some oil is getting consumed. I was the low oil light come on later on today..
The oil pressure gauge was fluctuating a bit today..
When it was at 22-25 psi and I went WOT, it climbed to about 40psi, but seemed to quickly go back to 35psi then again quickly back to 40-45psi....
Also, as I mentioned before, some oil is getting consumed. I was the low oil light come on later on today..
I have similar oil pressure as you when using 10-30 Mobil 1 or Pennzoil Platinum. Though mine goes up to about 50 @ WOT when the motor is really warm. My low will also be at arount 20-25 at idle. Considering we both got our motors from TSP that might mean they are normally like this...Have you tried contacting them and asking about this?
I have tried Pennzoil vr1 20-50 and it does seem to add more pressure to the motor when hot but almost seems like there is just too much pressure when it is cold (the guage almost all the way to the top) I ended up mixing 3 quarts 0-50's and 3 quarts 20-50's to make an even 10w-50w. It seems to work pretty good at keeping my oil pressure within the correct limits or so I think considering I'm using the old stock oil pressure sending unit and judging off the stock guage.
#35
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What would this mean is wrong with the engine? This is exactly what my car is doing. I have a 2012 CTSV wagon with this problem. and a few other odd issues but I noticed this one recently along with some odd metallic rattling upon revving hard.
#37
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Odd metallic rattling when accelerating could be preignition, AKA pinging. After enough of this, your lower end falls apart, which might explain oil pressure fluctuations.
#38
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Thanks for the response.
Any idea as to why I would be having pinging? It literally happens on command. I am in neutral, rev the engine hard to about 4500rpm let off and hear what sounds like a kid playing with keys or a necklace jingling near the front passenger side of the engine.
Any idea as to why I would be having pinging? It literally happens on command. I am in neutral, rev the engine hard to about 4500rpm let off and hear what sounds like a kid playing with keys or a necklace jingling near the front passenger side of the engine.
#39
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Wait; it pings when accelerating, OR when you let off?
#40
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put 20w-50 vr1 in it. as long as your psi increases as soon as you touch the throttle then your good.
Sounds like your motor was built a little on the loose side.
mine is .003 on the rods and .0025-0028 on the mains. plannig on running 20w-50 this time around. Previous builder put everything to stock specs and said run 5w-30 lmao. 1200hp motor. great idea. at the time i didnt know any better. stupid me
Sounds like your motor was built a little on the loose side.
mine is .003 on the rods and .0025-0028 on the mains. plannig on running 20w-50 this time around. Previous builder put everything to stock specs and said run 5w-30 lmao. 1200hp motor. great idea. at the time i didnt know any better. stupid me