RV Expert Center
Tips for checking dual tire pressure on your RV
Valve stem extensions can make reaching the valve on the inside tire easier to reach. They add about four inches to the tire valve so you'll be able to reach it and get a true reading. These stem extensions are specifically designed for dual-tire vehicles and run about $15.
However, valve stem extenders can only be used on metal valves and some tire experts warn that they can increase tire air leaks.
A dual foot pressure gauge often used by truckers is a good option as well. It looks like a regular tire pressure gauge but is longer and has an angled stem to make reaching the inside tire valve possible.
Filling dual tires up is another issue that takes some planning, according to the website. Most regular service stations won't have the proper set-up. Truck stops will be the best option for getting air for dual tired vehicles.