We demonstrate a clever and easy way to add air to high pressure tires on a diesel pusher motorhome using the on-board air system.
With lots of modern equipment, full-wall slide-out mechanisms, tile floors, etc, newer diesel pusher RVs are heavier than ever. The front axle in particular, supported by only two wheels, places heavier demands on tires, and often requires very high air pressures as a result.
Checking tire manufacturer’s tire pressure charts shows that the greater the weight placed on a tire, the higher the air pressure needs to be.
Since the maximum air pressure available from a diesel air system is about 120 PSI, that can make putting air into your tires a challenge, mainly because the system does not STAY at 120 PSI. Truck and RV air systems are designed to routinely cycle up and down between about 90 PSI and about 120 PSI.
If your tires and weight require 110 PSI, and your air compressor is currently at 105 and not running (air pressure cycle is on the way down), there is no way to get 110 PSI into your tire from a 105 PSI source. It will let air OUT of your tire instead!
We demonstrate how to assemble a simple, elegant and inexpensive solution to this problem from parts available at a typical home improvement store.
UPDATE! After watching this video, check out how we improved our set-up even more, allowing it to be operated by one person:
UPDATE: High Pressure RV Tire Inflation
UPDATE #2! If you want to avoid the time and effort of assembling a system like this, check out the new way we inflate our tires:
Guy Cambone
Saturday 10th of October 2015
Just joined your site and love the tips and advice. We've been in RV'ing for the past 4 years and just sold our home and are full time starting in May. Watching your tire series was very educational. What grabbed my attention was the way you were able to clip on both your tire gauge and leave it basically hands free. My question is what type, make or brand, are the caps your using. Being able to check and fill or release air without removing valve stem covers caught my eye. I've tried every search combo I could think of without finding ones for big rigs. I'd appreciate the information. Guy.
TheRVgeeks
Saturday 10th of October 2015
Hi Guy! Thanks so much for the nice comment, and congratulations on going full-time! The flow-through valve stems are here in our Amazon store:
https://www.thervgeeks.com/our-favorite-gear/double-seal-inflate-through-valve-caps-4-pack/
The ability to put the chuck on and leave it there is actually a function of the chuck itself, which has concentric rings inside to catch onto the valve stem threads. We got that so long ago, not sure where, but it might have been a truckstop or auto parts store. You'll know when you see it, since it won't be smooth on the inside where it connects to the valve stems. We don't actually use it any more, since we invested in a Viair compressor: https://www.thervgeeks.com/product-recommendations/inflating-rv-tires-made-easy/