Losing Tire Air Pressure

All,
I need input from this board regarding tires losing air pressure. The tires on our coach was relatively new when we purchased. At the time of purchased I had the dealer install the Pressure Pro system. The coach has been sitting four weeks. I went out to the coach today and three of the tires have lost 30 pounds of air. The outside tire on the drive axle on the driver's side has been a continuous problem. Marathon replace the core of the valve stem on this tire in June, but that did not correct the problem. Are the sensors causing the air leaks? I am perplexed about this situation.
We have owned four other coaches and none of them has presented the problems that we have experienced with these tires. Any and all suggestions will be greatly appreciated.

Reese
2007 Marathon Coach XLII #1025

The problem could be the valve stems or extensions. It definitely will not be valve cores as they are held open by the TPMS sensors. If you want to determine if its the sensors is pretty difficult without moving the sensors.

Take them off the bus and 1 at a time soap them up??? I'll be making my annual November pass through Texas again Reese if u don't figure it out we will get to the bottom.of it then.

Joe and Gil,
Thank you for your responses. This situation has become frustrating.

Reese

Just caught the fact tires were installed at the same time. Take the sensors off and see if you still lose air. This will tell you if it's the wheel/tire or valve stem/sensor.

Reese if u pull the sensors and they still leak............
I have a local tire shop that still uses the big round galvanized pool they put mounted tires underwater in to find leaks. They have a hydraulic ram with fingers that push it under and hold it. I bet there r also local tire shops in your neighborhood who have them. Call around find a place and put the tires in the dip tank u will for sure get to the bottom of it.

Great advice! Love seeing the help that is so readily and knowledgeably offered...with nothing but the intent to help! The rest of society could stand to learn from the examples provided in this forum and community. Can’t wait until we have our coach (heading out this weekend to make selection from several)!

Greg & Deb
WinterStorm

This will not be your problem since one of them is the outside dual. However, my inside drives are steel wheels and the tire shop that Fort Worth Prevost called showed them that it was actually the old wheels that were leaking.

Reece,

Remove the sensors and then see what you have. I’m repeating myself from the other side, but for those not familiar with Pressure Pro, the only sensor leaks I’ve had in many years was with 2 sensors that I checked myself and found a leak at the seams. These caused a very slow leak and I replaced under warranty. The one with the underside leak was hard to find.


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All,
Thanks to everybody for their responses to the loss of air question. It is appreciated.

Reese
2007 Marathon XLII

I had the same issue on inner drive wheels. The extenders were the problem.

Fratto,
Which tire shop did Ft. Worth Prevost refer you to? I will probably need to contact them. Thank you for your reply.

Reese
2007 Marathon XLII #1025

Rootdmd,
Thank you for your response.

Reese
2007 Marathon XLII #1025

Reese, I had the same issue a couple of times. It was the valve stems each time on the inner dual. Of course it couldn't be the outer dual on tag or steer tire.

Reese, sorry I missed your post. I am not sure who the tire shop was. Prevost brought them in as a 3rd party vendor so I did not have to worry about it.

Loc and Fratto,
Thank you for your responses. Been to the coach three times and checked pressures with PressurePro and the air pressures have not dropped in the last week. We will see what develops.

Reese
2007 MarathonXLII #1025