this is number 1mechanical gauge and seeing what actual pressure is.
never trust a gauge.
i didn't see engine or mileage posted.
if its over 100k i wouldn't use 5 in anything i owned. id switch to 10-40, or depeindingn on climate and mileage straight 30, or 20w-50.
BUT you said idle at 10psi and 30 while driving is really all a bone stock engine ever needs.
Rule of thumb, if it doesn't make any noise, its good.