Are you saying the lowest it ever goes is 22psi? (hot/idle/in-gear/foot on brake?). Is that measured with an actual (good) gauge? Or from the truck's sensor?
You might try:
1) A 0-60 or 0-100 psi calibrated gauge. (higher pressure gauges can be less accurate on the ends (most accurate in the middle range).
2) Make sure you bleed the air out of the O/P tester line.
3) Try a different filter. Better one. I recently had a filter come apart on a vehicle I changed oil on ...that can happen too.
4) Perhaps add a qt of thicker oil, see what that does.
Those things might make a difference. You could also raise your truck's idle a bit too.
Everyone wants to have higher oil pressure just like everyone would like to have a little more money. While yours is lower than many, it's still within what's considered 'ok'. I once owned a Ford tk which the oil pressure would go down to 4psi...and yet it ran great down the road. The oil pressure in my H3 has been around 10psi (at it's lowest on a hot day) for years. Bearings are getting loose. At first it bugged me, I don't like low oil pressure either. But as the years went on she still runs and I drive it most days. It's probably been like that 5-6-7 years, IDK ..maybe longer?? It was owned by someone else before. Guess what? The sun still comes up in the East and sets in the west every day, and I put a bunch of miles on it since I first discovered it.
