low mile 1993 3.9 Magnum oil pressure problem.

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Dec 7, 2019
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My heart is in Dixie
So the dakota was well mantained truck. valvoline dura blend 10w30 vwb 5/10w-30, every 3,000...
So I bought it to pull my trailers and winter 4x4, maybe have put 750-1000miles on it.
two three 100+mile trips with 14' tandem with idle time ran great.
one 3.5mile trip unloaded trailer lifters collapsed and lost all pressure. loaded trailer started with low oil pressure on gauge drove slow home with lifter noise.
sat a week and started with good oil pressure and lifters pumped up. let it idle 2.5hrs good pressure drove 15miles with good pressure to mechanic.
he changed the oil and pressure switch, said he drove it hard loaded a trailer heavy and drove hard and had good pressure, he was stumped.
100+miles towing boat after that and alot of idle no problem.
last trip half hour idle to temp drove 4miles 55mph pulled into my friends and lost all pressure. let it set five minutes started with some pressure but wouldnt pump the lifters up. shut it down 10-15minutes started up with good pressure 1.5-2minutes quiet as a church mouse. let it idle about 2hrs and drove 4miles home good pressure.
i am stumped!!!
 
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Sep 20, 2016
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MN
The lifters ticking is a good sign it is actually low on oil pressure and not just a goofy gauge or sender. Do the oil pumps on those have a tendency to stick the relief open occasionally? That's about the only thing I can think of which would make this such a random issue that seems to reverse itself at times.
 

bithebay87

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Dec 7, 2019
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My heart is in Dixie
Ramd maintenence records at purchase.
thanks Chris142, it did have the pan off at like 65k to clean screen. that with 3,000 max ocis
thanks Tman220 that was kinda my thought.



-harvey
 
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Jan 4, 2016
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Why are you towing anything with that anemic V6? Especially heavy.
Oh boy, you'd be surprised to see what 2.4L 4 cylinder Frontiers from the early 2000s pull around here for construction workers. I bet they pull more weight in a day than 99% of local Brodozers pull in a year, combined. So yea, that little V6 is more than enough for people that actually do work and pull stuff.
 
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Oct 9, 2004
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Cincinnati, OH, USA
Ramd maintenence records at purchase.
thanks Chris142, it did have the pan off at like 65k to clean screen. that with 3,000 max ocis
thanks Tman220 that was kinda my thought.



-harvey
Think I would bite the bullet, pull the pan & clean it, put on a new oil pump & drive/intermediate shaft (HV if available). Sounds like too good a truck to risk blowing it up to me.
 
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Joined
Feb 26, 2013
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Why are you towing anything with that anemic V6? Especially heavy.
One ton trucks had sixes in them back in the day. I have a 4.3 in my 2012 Silverado and it's done some overloaded towing for sure. These motors can take a beating, but I would put a new oil pump & pickup in that Dakota.
 

bithebay87

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Joined
Dec 7, 2019
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My heart is in Dixie
i am gonna pull the pan, clean the sreen and pa and replace the pump with hv/hp pump and repace the drive if it shows wear and do a delvac extreme 15w-40 mmo cd2 fill with a ST-8A filter to clean the lifters and top end along with plus and pvc...



-harvey
 
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