Low Oil Pressure

[The FNG]

Hi All,

So two oil changes ago, I switched to Valvoline 15-40 because it was on sale and I was low on cash. I normally use Delo 15-40. About 800-1000 miles into the Valvoline, my oil pressure dropped on the dash gauge from about the middle of "NORMAL" to just below the "N", but still within the range I guess. I left it where it was and changed back to Delo at the 3000 mile mark and after about 200 miles, the oil pressure went back to the middle of "NORMAL". Now, just under 1000 miles in, the pressure is back below the "N". I have probably been letting this go too long anyway, but it is beginning to annoy me.

I would like to test the pressure manually, but I really don't know where or how. What should my pressure be? Do the dash gauges fail often? How about the sensors?

Thanks!

 

[icanfixall]

The dash gauges are an idiot lite with a pointer.. Pay no attention to what they say. Your not the first owner with this same question either so don't feel your being laughed at. I was watching my oil pressure gauge many years ago fluxuate up and down as I drove down the road. I installed a real mechanical pressure gauge and found great constant oil pressure as the dash gauge went up and down... All the dash gauge is telling you is that you have oil pressure... Not how much either. Its only design is to reconise pressure and report it to you... Its a very poor factory design but works for the common driver well.

 

[Trying my best]

I had the same thing happen to mine, it wasn't after an oil change, but the gauge would sometimes work and sometimes not. I ended up putting a real gauge in the cab of the truck in addition to the factory gauge. I finally traced the faulty gauge to a bad connection between the sending wire at a connector under the master cylinder.

Good luck

 

[GOOSE]

Just finished installing my aftermarket oil pressure and engine temp gauges. I feel very relieved to be watching what is actually going on rather than having no idea what the "O" in normal means. I actually grounded the wire for the stock oil pressure gauge so it comes up and the red engine light stays out. Worked like a charm I can post pics of where the sensors are if you are really interested.

 

[The FNG]

Pictures would be awesome. Also, what gauge setup did you use and how does it look?

 

[Dieselcrawler]

I have a pic of the motor with all electronics labeled. Can post it when I get home

 

[RLDSL]

You can bet the sender is due for replacement if they start reading squirrily like that , it's almost always the sender, otherwise a loose connection or wire thats about to break. It's at the back of the intake on the top of the block. If you want to put a real gauge in you can put a T in there or just eliminate the factory one or there are a few other spots on the engine that you can tap in.

 

[dansvan]

Or put a real sender in from an earlier truck and solder a wire around the resistor on the back of the instrument cluster. Returns the guage to its normal originally intended function