I have a 1996 F-150 5.0L, V 8 with 217,000 miles with no serious problems except:

-I am getting a low oil pressure reading on my oil guage. Sometimes it is in a normal range and other times it is damn near all the way to the "L". It has never leaked or burned oil. I put Mobil one Full Synthetic 10W-30 in it. Could this be a potential sensor problem, oil pump, or is my engine going to go?

I also have a squeaking noise coming from my truck whenever I first start it up. After about 10 minutes the squeak goes away. I have installed a brand new belt and I am guessing it is a tensioner or pully? Any suggestions?

Thank you

 

check with mechanical gauge, dash gauge is a glorified idiot light.

could be a clogged pickup screen.

 

The dash gauge is nothing but a fancy idiot light it's not a real gauge so it's not really showing you how much oil pressure you have.. just that there is some. And unless you can hear the engine making tapping or knocking noises there is no oil pressure problem, so clean the sender wire and terminal and/or replace the sender.. it is down on the block in front of the oil filter.

 

I had the same problem on my 92 F-150 and it was a clogged oil screen. If you are maintaining a good oil level I would probably think about doing the oil pickup screen, pump and oil pan gasket if you really feel the need. Just like Conanski and quicklook said it's a dummy light. They can be a bit of a pain to replace but when I did two of them it brought the oil pressure back up to normal. Listen for a knock before you go that deep in on maintence though...

 

Just to confirm....the gauge on your dash is activated once oil pressure is about 7 lbs if I remember correctly. Any deviation would represent a bad sender or bad connection...likely at the sender.
The gauge should either not show anything or be dead center.
I would do as Conanski said and check your sender and/or connections

 

Thanks guys! Any suggestions about the squeak?

 

Hard to say provosc....
you can use an automotive stethoscope or a hose or tube(used as listening device) to help you narrow it down.
You can also remove the belt and see if it still squeaks when you fire it up. If not, then you can start looking at your pulleys or belt.

oh..and by the way......Welcome to FTE!!!
Stick around and you'll find lots of good stuff here.
wherever possible...always follow up and post your outcome so others may benefit.

 

Thanks man! I will take my belt off and go from there. Exellent information from knowlegeable peolpe. Much appretiated.

 

I'm with ya'll on the oil pressure gauge. Mine is always between N and R. I'd expect a little variation especially with the hot Dallas Summers but Id didn't see much. It definitely isn't real time.

My '01 Durango OP gauge fluctuates depending upon engine RPM - which it should.

Yup - in my F150 it's a glorified idiot light.

I'm going real gauges after my high priority items have been completed.

 

I vote clogged pickup screen. I've driven several trucks that had one.

One was a great looking 351W that lost pressure at idle when hot. It had a clogged screen, but the owner was a real tool and kept trying to say I was retarded. Passed on that one, lol.

The factory sender grounds at 5-7psi, which is pretty low, but just enough to be safe. Most folks install a mechanical gauge when these trucks get up in years. I checked mine when the sender blew out but didn't want to run a line in the cab, so I just replaced the factory sender.

 

A clogged pickup will show itself at cold start up, and high engine speeds (high viscosity and high flow conditions, respectively). If it only loses pressure at hot idle, chances are that the problem is something other than a clogged pickup.

 

My 94 is the same way. I picked up a new sensor since it was only 6 bucks, plan to instal that on the next oil change. Also waiting for a friend to get time to replace my wrotted out oil pan, so while it's out I plan on doing the oil pump as well, considering not replacing a thirty dollar part on a big project like that could only lead to kicking myself later.

 

new pump and new oil pickup and felpro blue one piece gasket.

 

Turns out that the alternator wheel was bent causing it to make an annoying squek. Problem fixed, thanks for comments.

 

Glad you got it worked out....