1992 toyota pickup 3.0 v6 4x4
the trucks got 212,xxx miles i know shes probably getting tired but when i start the truck in the morning the oil pressure sits at about half way (in the middle) but once the truck warms up and after running it for a while the oil pressure drops to the first mark on the dash. (like the 1/4) mark. it will go up a little but not until i get up into the 3,000 rpms area. im running a sythetic 5-30 in it right now. would a higher grade oil work better to help the oil presure. like 10-30 or 10-40 or even a 15-40? and help would be appreciated. thank you

 

This might answer some of your questions: https://www.yotatech.com/forums/f116...icture-288793/

Without hooking up an actual diagnostic gauge you're kinda guessing at the oil pressure. The factory gauges are more of a happy/sad type of arrangement. That said, you could also have a weak signal or lame sender.

 

That condition is extremely common. The post above is right about the inaccuracy of the gauges. Don't consider the upper line as 75% and the lower line as 25% and more is not necessarily better. A non SR5 wouldn't even have a gauge and the pressures that you are seeing would not set off the low oil pressure light by a long shot.

Mine does exactly the same thing. After 40 miles of highway driving, it will be right down on the lower line but never falls below it. It used to by just a little before I started using 10W-40 in it. That 5W-30 you are using is too light. As engines wear, tolerances become looser and a thicker oil will usually cut down on some of your leaks, blowby, noises etc. I cant remember for sure but isn't 10W-30 the recommended viscosity for this engine? Lots of folks even use 15W40 in them. Most of the mechanics that used to work for me had old Yotas and all of them used 15-40.

I would like to hook up a live gauge to mine just to make me feel better but after one of my buddies, who is an excellent mechanic, tried that on his and broke off the sender in the block trying to remove it, I have made peace with the seemingly low gauge reading.

 

Oh that's a cool link I haven't seen yet. It's missing the engine off picture where the oil gauge needle sinks below the bottom line but still very handy.

 

The 3VZ engine, as you know, is a single overhead cam design valve system.
Because the engine doesn't have the hydraulic lifters, push rods, and rocker arms that a cam in block design has,there is no need for the high oil pressure that these components require.
After a rebuild, I put a mechanical gauge on my motor after it was broken in, and measured 16 psi.at idle on a hot day, and 40 psi at 3500 rpm on the freeway.
This was using Mobil-1 20/50 synthetic. The idle indication on the stock needle was a little less than 1/4, and the 3500 rpm reading was about 1/2 way on the needle.
That was about 60,000 miles ago. It has never changed, and has never given a problem.
Your indications appear to be normal.

 

Lot of good info here. I don't know how long you have had your truck but if it's new to you, and you decide to step up your oil viscosity, I wouldn't go with a synthetic unless you know that it has been running synthetic for the last 50K or so. A switch to synthetic at high miles will often show you all of the leaks that you didn't know you had.