I finally had an opportunity to getting our coach weighed (axle weights only) and would appreciate a second look to check what I’ve done to confirm my understanding is correct and I’m not underinflating my tires.
Front Axle Weight: 9,720 lbs.
Rear Axle Weight: 16,140 lbs.
TOAD (Honda CRV with 4 Bikes on Rack): 3,960 lbs.
TOTAL = 29,820
Tires: Michelin XZE2 275/80 R22.5 Load Range G
The inflation tables are
here.
If I’m reading the inflation table correctly, minimum pressures are as follows:
Front Axle: 80 PSI
Rear Axle: 70 PSI
These are much lower pressures than I expected.
Not knowing the weights, I have been running 100 PSI all the way around. This weekend I've reduced pressure to 90 PSI front and rear.
I only had half a tank of water and completely empty holding tanks when I weighed the RV. Add another 100 gallons of water between fresh and waste tanks (leveraged WAY behind the rear axle) I'm assuming another (worst case) 1500 lbs. on the rear axle. Throw in another 5-10 PSI for left-to-right differences in weight…and you’re somewhere near 90 PSI on the rear.
On the front, I added 10 PSI to account for potential differences left-to-right plus a margin of safely when holding tanks are full.
Two things surprised me:
- How much my CRV weighs with 4 bikes on the back!
- How much nicer this thing drives with 90 PSI in the tires vs. the 100 PSI I had in there previously. Much less harsh over pavement imperfections.
I did all my pressure adjustments this past weekend as I installed a new TST 507 TPMS system. Set all my thresholds based on 90 PSI. I’ve only driven an hour with it so far, so I’m sure I have more to learn.
I do intend to get this thing re-weighed next time I have an opportunity when all tanks are brimming, but in the meantime, I'd like to take a conservative approach.
Thanks for any insights.
Tom
2012 Jayco Embark TB390
Blue Ox Aventa LX Tow Bar
2009 Honda CRV (mini toad)
2014 Ford F-150 4x4 (monster toad)
FMCA #F413428
