jzawislak86f150

Hey there guys, I have a red 1986 f150 extended cab SHORT bed. It's got a 5.0L automatic, with a rebuilt front end,and rebuilt transmission. Runs and drives pretty damn well, but recently I've been having problems with my oil pressure. The truck fires up right away but at idle the oil pressure is low, and when I'm driving it goes up (yes I know it's supposed to do that). But it's lower than normal at idle, and when I'm driving it doesnt rise back up as far as it should. Stopping at a stop sign the oil pressure just drops too low. It doesn't die right away though, only after a couple of minutes. I'm no expert on this kind of stuff so any help/suggestions is appreciated.

Thanks you,

Badger150

I've got a similar problem. The first step is to check the oil level, since if you're low that could give you these symptoms. Assuming then that you have the correct dipstick (Jiffy-Lube guys sometimes swap dipsticks) and the dipstick tube is correct (the one in my truck was wrong, but I'd say this is a rare occurrence), the three three things I've been told to consider are (in no particular order):

1) Faulty gauge. If the gauge is as old as the truck, it may just be reading artificially low. Check the oil pressure with another gauge and compare. (I know this can be done but don't know how.)
2) Faulty oil pump. I know in mine the engine has to be lifted to pull the oil pan as a necessary prerequisite for pulling the oil pump.
3) Try a different weight oil, keeping in mind that a heavier oil will have more difficulty getting to the more distant parts of the engine.

From reading other threads, I see that Seafoam Motor Treatment is recommended by several users for cleaning out the oil passages within the engine, which may be applicable here: http://www.seafoamsales.com/sea-foam-motor-treatment/

Hope this helps,

- B

diyautoelectric

Just raise the idle
Actually both of your problems are worn bearings, you can use thicker oil and it will help. And if you baby the truck it can run like that for a long time.

Badger150

Which bearings?

JayzDaddy

Crank and rod. The whole engine is getting a larger gap than spec just from wear and tear. Thicker oil can help some but in the end like all high mileage engines it will need rebuilt/replaced. Its possible the rings are causing the problem too. Creating blow by. If you need plugs keep the ones you pull in their proper order then compare. If one has a bit more oil or stain on it that cylinder is leaking. Its just nature taking its course.