High oil pressue cold start

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Topic author
RustyDusty
Posts: 35
Joined: Wed Nov 06, 2019 8:55 am
Location: Northern VA

High oil pressue cold start

Post by RustyDusty »

My oil pressure is very close to 80psi on start up, but then calms to around 40 for normal driving. Is that normal, or if not, what should I be checking on to fix the problem?

Thanks,
1990 Grand Wag
R4B/Holley 4160
I might lament the amount of grease and oil on the underside, until I think about the lack of rust.

candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: High oil pressue cold start

Post by candymancan »

Could be a bad pressure sender. My sender pegs to 80 sometimes and othertimes it works right. I gave up on knowing the oil pressure on my engine. Now i just go by what it sounds like lol.

But prior to it going bad when it worked. My oil pressure on a cold start would hiver around 60psi. Then drop down to 40 at idle after it warmed up a little.

When driven and nice and hot my oil pressure in drive sitting at a stop light is around 20-25 psi. When driving at 45mph its at 45psi. When on the interstate itll be around 50-55psi. This is using 10-40 in the summer and 0-40 in the winter.


As for what oil i use. Winter i use that 0-40 european car formula for better flow on the cold weather and a cold start. Summer i use 10-40 and whatever brand is cheapest usually the walmart or valvoline synthetic blend or stp. My engine honestly sees like 6 different oil types yearly.. lol. Same goes for our 4.0 Grand Cherokee ZJ as far as brands go i mean whatever is cheaper. And that engine has 305k miles now.

Right now i have the rotella t6 5-40 because they were selling 3 4 quart jugs in autozone for like 25$ for all 3 jugs.
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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