Oil Pressure Question

[Rex2nr]

I just installed an oil pressure gauge (Autometer Sport Comp) in my 99 4.0. My sending unit failed last week, and had the gauge sitting around so, why not?

I searched around but couldn't find any numbers I be seeing? I am currently reading around 60psi at cold idle, 40 at cruising and around 20 at idle. I haven't gotten the backlight installed yet so those numbers may not be 100% accurate, but definitely in range. There is 200200 miles on the truck currently.

 

[hank857]

sound about right and actually fairly good for the miles.

 

[Rex2nr]

so I can't yet justify the 5.0 to the wife.... dang!

 

[pjtoledo]

tell her those are metric numbers so you really do need another engine

 

[adsm08]

Yeah, that sounds about right. Those numbers are consistent with my 4.0 that has less than 15,000 miles since I rebuilt it. I don't even see 60 on cold start. I sit around 40-45.

 

[Shran]

I concur, sounds very healthy.

My rebuilt 2.3 shows as high as 85 when cold at highway speed, 60ish cold idle, around 50-60 warm on the highway and around 25-30 warm idle.

 

[adsm08]

On the other hand, there can be other wear issues that aren't reflected by oil pressure. You could have low compression.

 

[Rex2nr]

I did a compression test last summer, all cylinders were right around 120. I did head gaskets when I first got the truck July/August, 2015, and the cylinders looked great- still had the cross hatching on the walls with some minor carbon build up. I'm very surprised with the condition of the engine at this age, and was pretty concerned because of the state it was when I bought it. I drained around 2.5 gallons of milkshake when I did the head gaskets