What is the maximum allowable tire pressure differential allowed for part 119 operators?...can you yourself just check with a gauge
Tire pressure should be checked atleast 2 hours after the last operation with a gauge at ambient temperature. A temperature-sensing valve in each tire can release air pressure on aircraft as well.
I found relevant info on tire pressure differentials in FAR 21, 23, and 25.
I look forward to hearing a more thorough response from anyone who knows.
p.s. even with Nitrogen filled tires there will be temp dependent pressure changes that can be modified by a sensing system.