At start up oil pressure is 40 but after 20 minutes of driving it drops to 10 at idle ( My idle is around 600 RPM ) and at cruise it's around 20-25..I took it to a shop and they told me it's normal and there is no noise at all.. And that there is nothing to be worried about as far as bearings.. I'm currently running 5w-30 oil and a Fram filter if that helps.. Should I just stop worrying or is there a problem.. I know it's not the main bearings ( Thank God ) but could it be a sensor.. Oil pump.. type of oil.. etc? Or is everything normal? I'm new to Chevy trucks

 

What makes you so sure it isn't a bearing problem? I had a 94 Suburban with a similar oil pressure issue. It spun a bearing. However I admit that might not have been what was causing the low pressure at idle. I've been told that the oil sump pickup in the pan might have been dislodged or poorly installed and only partially sucking in oil. How hard is it to drop the pan and take a peek?