My 03 ram 360 magnums oil pressure gauge goes crazy when I start braking off the highway mainly, sometimes when I get on it and stop shortly after. It will rise slowly til it gets close to the max on the gauge then drop all the way down and continue to do so if I'm stopped at a light. Engine doesn't make any noise when it drops and sounds exactly the same when pressures at max. As soon as i hit the gas my gauge goes rightrback to the middle. Tried to do a bit of research and talking to people.. sending unit was replaced about a year ago by my dealership. cleaned my throttle body and replaced plenum. Plenum made a big difference in how well it holds oil. Still burning and losing oil some how. No one has found any oil externally. I haven't tried hooking a mechanical gauge up yet. I'd love it if I could keep oil in the engine and it not turn dark for a while at least. I know you guys got some ideas

 

Sounds like another failing sending unit.....

 

So I replaced my sending unit(again) after i did an engine flush and oil change... I drove to town to get some smokes after I did it. No craziness on my gauge at all and then I get back home and watch it for a second as it's idling since that's when it seems to happen. Of course, it rises slowly(slower than normal)' then drops and says check gauges and goes back🤤 I get a puff of black or blue smoke when I romp it after a cold start so I'm narrowing it down to a few things. 1. bad valve seal/s. 2. bad piston ring/s 3. A cyclinder head cracked internally 4. Bad oil pick up tube. Any other advice on the subject is very welcomed. My truck doesn't make any commotion when the gauge goes bonkers...

 

Wonder if there is pressure safety valve involved with the oil pump setup....

 

The pump has a pressure relief valve, as it is capable of putting out a LOT more than the 60PSI or so you see on the gauge.

I would put a mechanical gauge on it, and see what oil pressure is really doing. My guess is, it's just another crappy sending unit.

I had a Honda Accord, way back when..... that the relief valve on the oil pump seized..... so, the system would get FULL pump pressure right from the get-go. As soon as you started the engine, the oil filter would become spherical, and then pop loose at the seam. Really made a mess.

 

I'll try n hook up a gauge today or tomorrow.. but is it possible for that release valve to get stuck or not open/close all the way?

 

If it was stuck, your oil pressure wouldn't fluctuate at all. They are notoriously very reliable.