I tried doing a quick search but didn’t exactly find what I was looking for. So the hellcat/Melling oil pump seems to be the “fix” for low hot idle oil pressure but would tuning the hot idle in park engine RPM be a much easier solution? I’ve got a 2020 5.7 rebel and it idles at what looks like 550 RPM when at full operating temperature with 33 psi. Just lightly pressing the pedal and getting the RPM around 750 RPM increases the oil to 45 psi. It seems that you could just have a tuner increase the idle RPM to around 750 and solve the problem. Installing the Melling or hellcat oil pump is in my wheelhouse but it’s still quite an undertaking. I think that increasing the idle RPM in park would solve a lot of the low pressure problems. Does anyone have any thoughts on this or if you’ve done it? Thanks.
If the truck is not indicating an oil pressure issue with a warning light, and the oil pressure gauge is not indicating any issue, then you have no issue. From a comparison of other vehicles we have owned and still own, I can tell you that 33 psi at idle when the oil is hot is actually in the higher range. Some of the Euro cars will go down to high single digits.
Other thing to note, and I am not sure how it works with the Ram but it is very unlikely that you can change the idle RPM. This is going to be set by the engine management computer based on the inputs it is receiving from various sensors.
As far as idle hours go, my understanding is that the idle hours is showing engine running but car not moving. On my truck, idle hours are slightly less than 10 percent of total engine hours. But I also make a point of not idling any of our vehicles if I can avoid doing so because I don't like to waste fuel. If you have to run more time idling, I would follow the severe service schedule in the manual and make a point of using a high quality, full synthetic motor oil. The synthetic oil will resist degrading more than a semi-synthetic blend. I would also stick with the 5w20 rating that is spec'd, as going down to 0w20 will only lower your hot idle oil pressure, even if only slightly (if this is something you are worried about).
HTH.