Recently, I've noticed my oil pressure dropping a bit lower than usual. Typically, my psi was always 40-60 while driving, and never below 20 when idling. I've noticed recently while idling that my pressure is dropping to about 16-18 psi, and lower when driving. I have 125k on my truck and recently moved down south to Florida, where it's pretty hot.
I use 10w-30 oil - had it changed 2,000 miles ago. It's due to go into the shop in May to have some work done to the exhaust system and engine. I do have a bad knock when idling when the engine is cold, but it disappears after the engine has warmed up. (about 10 minutes) I think it's more associated with needing to replace the fuel injectors/regulator than anything else. However, I could be wrong.
I checked my oil level today - looks good. The oil is a light brown color - I am guessing this is OK?