I have a 86 ford f150 302 v8 5.0l it loses oil pressure after the truck warms up and im not sure what it needs, it doesn't lose oil just pressure, any help would be great

 

Put a aftermarket guage on the engine to see what the pressure really is. You can get them at the parts store for about $15.00.

 

and after that what if its still loosing pressure? is it the pump or something more dire

 

What are the pressures at hot and cold?

Jared

 

JC Whitney sells a mechanical gauge for like $6.

 

johndoe_1_99, If you still lose pressure with the mechanical gauge, more than likely you have some worn bearings.

 

Yes as the oil warms up you will lose some pressure, if you are experianceing total pressure loss then you have a real problem.

 

hoe old, and what weight is your oil?

Use good clean oil of the correct grade and check the pressure.

 

 

[updated:LAST EDITED ON 07-Nov-02 AT 11:07 PM (EST)]I have an 86 F150 and it also does the same thing toe more i keep the rpm's up the gauge will go up at park it will fall. I have driven it for about 6000 miles so any foreseable problems?

5.0 302

 

I just bought an '86 F150,5.0,302 at an auction
with the same problem. The pressure starts out
good then goes to 0 when the engine warms up.

 

but when you are on the gas does it go up at all?

 

sometimes after I stop and take off it will move some (up to the L or barely into Normal)but the majority of the time, once the engines warms up it doesn't move at all. There is a leak that I havn't found yet. Could it be the sending unit?

 

it could be I was told from a mechanic friend of mine that mine could be the sending unit, he told me how to check it but i can't remember now.

 

hey all i hate to say it but this sounds like an infamous problem

anyway i had a similar problem (when it would get to temp it would drop at idle or under load ) ---changed my sending unit and no change .i ended up putting a new pump in and reusing my pickup after a thourough cleaning but i had access to a shop lift and many tools at the time so i was fortunate .i still have a slight problem but it doesnt worry me ---when it idles in park or neutral at any temp(no load)it will hold perfect pressure ---but after a few hrs of driving and when the temp gets on the high side in gear only (under load) and only at idle it will slowly creep down to the 0 point but it wont knock or anything .in long cases of running like this i will bring up this rpm's to regain pressure on the gauge to feel safe ,and as soon as the rpm's are brought up it is fine


IMPORTANT TIP:dont do whut i did though dont go buy a high volume pump unless you know itll fit in youre pan bc i did this and it turned out even though the pumps seem the same the high volume where the shaft goes in to the pump it is slightly higher than the factory and makes the pump sit lower and wont fit into well a pan like mine anyway .

any questions on this just email me littlejuggalo17(No Email Addresses In Posts!)