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Discussion Starter · #1 ·
So I just put in a new mechanical gauge for my oil pressure and on startup I get about 50 psi then it goes down to 20 to 24 psi and after driving for a bit itll drop to 6psi and stay there whenever idling but there's no knock and no red engine light although I believe that my red engine light is broken, any ideas yall?
 

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Discussion Starter · #2 ·
I also believe I have a rear main seal leak which only leaks after the engine has been shut off if that helps
 

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1993 Ford Bronco XLT 5.0
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I just acquired a 1993 with a 5.0 doing the same thing. I put a oil pressure tester gauge on it first and once the truck warmed up no oil pressure. Next thing is to try a new oil pump an pick up. I seen it can be done without pulling the motor. Disconnecting the exhaust etc and lifting the engine some to have space to drop the oil pan down. Don't this its going to be fun.
 

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engines make least oil pressure when hot and idle. the rule of thumb is minimum 7psi per 1k rpm (so about 7psi at 700rpm)

doesnt mean you need to worry tho. it will run a long time on low oil pressure. but it will start to degrade more rapidly. you might start planning on a rebuild at some point in the next year or so depending how much u drive and how you drive. till then use some slightly thicker oil but dont go to thick. many people will run 20w-50 on heavily worn engines but it doesnt help that much. i dont recommend using oil stabilizer cause that turns the oil into honey consistancy. that puts alot of stress on the oil pump shaft and distributor gear roll pin. you dont want to break those

new oil pump n pickup may help abit but i wouldnt really bother unless its got a bad oil leak you are trying to fix also. the cause of low pressure is usually from worn bearings (rods, main and cam bearings) and crankshaft. they get excessive clearences and the oil basicly freeflows out ofthem and only way to fix that is pull engine and replace them. once you are at that point you mgith as well do a full rebuild.

the engine light doesnt come on probably because the facotry sensor is disconnected to use the aftermarekt gauge. the light will glow and gauge will read zero any time pressure is below 7psi. anything above 7psi and gauge will read in the middle and light be off

i have done bearings in vehicle twice. i would highly not recommend it. some people swap in a High Volume oil pump. thats jsut a bandaid for the actual issue and again puts alot of stress on distriburtor gear pin and oil pump shaft. also they dont always fit the stock oil pans
 

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Discussion Starter · #6 ·
Alright thank you, do you think 20w 50 might help give it a little more life? Right now im on 5w 30 motorcraft, and idk about the bearings the engine is 46000 original bc it was a ranch truck. Do you think an engibe flush might help it went almost 5 years without oil change so im think something might be clogged
 

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46K on a ranch truck could be 146K or 246K on a highway truck. I run 15-40 diesel oil in mine to help with oil pressure, although I'm using the dash gauge so I have no real numbers. Mine is mainly a summertime truck in Texas.
 

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Discussion Starter · #8 ·
I put some sae 30 oil in it and now im getting about 4-5 at warm idle and 22 at 2000 rpm is that good enough to limp the truck till I save money for a engine rebiuld?
 
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