on my 87 f-150 351 h. o. when istart it up it has 60 psi of oil pressure but after it gets up to operating temp it drops to about 25 psi and sometimes when you pull up to a stop sign it only reads about 10 psi could i have a bad guage or should i replace the oil pump any answers would be appreciated thanks

 

I have heard the gauges used in the trucks were not always accurate,you might want to check oil pressure with a mechanical gauge off the engine and see what it is,I had a 78 460 that would read low oil pressure after warmed up, I put a oil pressure gauge on the engine and pressure was within specification.Are their high miles on the engine.

 

i put a new set of guages in it because the factory guages wasn't reading right it's got 166k on it but it had new main bearings and cam in 1999

 

Oil pump could be getting weak with that kind of miles

 

i'm going to try and put auto- meter guagues in and get rid of the sun pro ones that are in there and i'm going to run copper line for the oil pressure instead of the nylon tubing.

 

but if that don't work i'm going to put in a new pump


p. s. old fords never die they just go faster!!!