Tire Inflation
I have a 2004 National RV Tropi-Cal Type A motorhome. A NHTSA recall of model-year 2004 and 2005 National RV motorhomes stated: “On certain motorhomes, depending on the floor plan configuration and options, the actual weight on the rear passenger-side tires could exceed the tire capacity for those tires at the current cold inflation pressure setting.” Can you tell me which floor plan is involved in the recall (35-, 37-, or 39-foot)?
National RV representatives told us to set the air pressure on all tires at 110 psi. The coach was weighed at an RV show, and I was told to inflate the front tires to 95 psi and the rear tires to 110 psi. I just installed new Michelin XZE 255 R80X22.5 tires. A Michelin representative told me that based on my coach’s weight, I should inflate to 95 psi front and 90 psi rear. Freightliner mounted the tires, and they told me 95 psi front and 90 psi rear as well. Can you help me find the answers to this?
Phil Arlotta, F280684
Faith, North Carolina
The vehicle certification sheet in your motorhome includes a recommended tire psi based on the gross axle weight rating — the psi needed to support the maximum allowable weight for that axle. To determine the optimum tire pressure, however, it’s necessary to weigh the motorhome, preferably by individual wheel position, as you likely had done at the RV show. So, I would follow those recommendations for the best ride and longest tire life.
Regarding the recall, as you no doubt know, National RV is no longer in business. The recall details on the NHTSA website (www.safercar.gov) do not indicate whether certain coach lengths were included in the Tropi-Cal tire labeling recall. The information does note that the recall was for models with a rear axle rating of 17,500 pounds and four tires that support up to 17,640 pounds at 95 psi. It goes on to indicate that depending on the floor plan and options, the actual weight on the rear passenger-side tire could exceed the tire capacity for that tire at the current cold inflation pressure setting. Accordingly, the tire pressure specified on the certification label for the rear tires was increased to 110 psi. This increased the gross load carrying capacity of the tires.
Again, it is best to have your motorhome weighed wheel position by wheel position by a company such as RV Safety & Education Foundation (www.rvsafety.com) and then use the weights in conjunction with the tire manufacturer’s inflation tables to determine the appropriate tire pressure. When you have the motorhome weighed, it should be loaded as it is for travel.
Stinky Coach
Every time we start down the road, our Tiffin Breeze fills with noxious odors from one of the waste tanks. The heaviest smell seems to be located mid-coach. The smell is not coming from the commode or the shower drain but is omnipresent in the hallway/galley junction.
Tiffin reconfigured the exhaust Venturi vent, which had been installed sideways at the factory, but that didn’t fix it. I replaced the Venturi with new highly rated roof vents, and while doing so and trimming the PVC vent pipe, I noticed that the outboard pipe was loose and would spin freely. I concluded that the junction where that tube attaches to the tank was never glued at the factory, or the glue failed, and that’s how smells escape into the coach. I debated pulling the vent line out, smearing the lower end with PVC cement, and lowering it back into its union. But I didn’t, fearing that I wouldn’t be able to blindly coax the goopy end into the union, and I might make things worse by melting parts with wet PVC solvent.
Instead, I opted to push and twist the vent pipe, snugging it down until I felt friction. Then I trapped it in place with the new Venturi unit, which I secured according to the instructions. That actually worked, temporarily. The smell was gone for our next several trips, but many railroad crossings and bumpy bridge transitions later, the smell is back.
My wonderful 2011 Breeze is no longer covered by warranty. They’ve been good to us at Tiffin Motorhomes all these years, but do you think I’m justified in asking them to warranty such a basic repair, especially as it is buried deep in the middle of the coach? Or, alternatively, how does an amateur access the very top of the black and gray water tanks through a one-piece plywood floor? This stinks!
Patrick Mulvany, F427701
LaGrange, Georgia
It wouldn’t hurt to ask Tiffin to fix it, especially if you have all the paperwork for the previous servicing. If they say no, since they are familiar with your coach, perhaps they could cut an access hatch in the floor to glue the vent pipe into place and then replace that hatch and repair the cut-up flooring material.