PSI lost

Took another look at the "GOOD TREAD TIRES"and found four to be 2005 and two to be 2010. The best fix. I bought six new tires. Kept a
2010 for the spare. :C

Good on you Beeman for checking your pressures and avoiding a tire failure on the highway!
I had a leak of about that rate of pressure loss on a minivan and it showed up clearly on the old soap bubble test. I took it to the local tire sop and paid $29 for fixing a tiny roofing staple hole. The fix failed and I kept driving on it for weeks (adding air every week) until convenient to take it to Costco where I bought it. There was a warranty with free puncture repair but the tire man refused to fix it because the outside of the tread had worn too low - probably due to driving with low pressure.

Use a Mixture of water and dish detergent in a spray bottle, just pick a tire and spray until you see bubbles. I agree, test the valve stem and valve first. The olde valve test is to spit on a finger and rub it over the stem end. VERY odd it is happening simultaneously to four wheels. Has to be a valve, stem or tire defect. Do you happen to have those recalled Michelin tires? That would be good news as you get free new tires!

make up a soap bottle spray every thing any leaks will show up.little soap in bottle but don't shake just spray & look

Also worth while getting a shrader valve tool to check they are tight. Found an outer tyre low and pumped up with my compressor after 3 days at a camp site and a tyre shop changed the valve (very slow leak stopped by fitting a dust cap from our motorcycle to get us to the nearest town). Thinking about it I went and brought a valve tool and checked all the tyres - found one not tight!

There was a big dustup a couple years ago over the discovery of zillions of defective shrader valves (what's in your tire valve stems). It seems a major Chinese maker had taken a shortcut that made those valves leaky. There's a good chance you've found a couple of them. The cure is just replace them. Valve stems and valves are pretty cheap.

j-d wrote:
Carefully, inspect the TIRE VALVES and any extensions, adapters, extender hoses that might be attached to the VALVES.

If those valves are rubber, they can be a source of leaks and possible blowouts just by themselves.

If the valves are rubber and anything more than a cap is attached, they become a time bomb.

The weight worries the rubber till it fails.

X10!

Been there done that.
All on ONE trip after purchasing a new to me used MH.

1. Blow out on one of the dually's that took out entire sewage bay!

2. And then 2 more flats I caught before they blew out from running on them low.

On the second tire going flat the tow truck driver pointing out to me that I had rubber valve stems on all the tires and between the 112 degrees heat of Houston and long driving times they were 'melting' from the heat and air was just coming right out.

That is what caused the first blow out. Air leaking I kept driving because I did not feel it and finally the tire just explodes. That tire ended up looking like it was a bad tire which it was not.

I pulled into the nearest tire shop and told them to take all the tires off and put on stainless steel valve stems.

Those tires on that MH should have NEVER had rubber valve stems on them. Just one more thing to CHECK when buying a used MH. :W

Cold weather affects tire pressure... I know my STATUS MONITOR goes off a couple of times every winter saying I have low pressure in X tire...

Roy Ken

Good points above also slow leaks from small nails. Sometimes this requires taking into a tire shop and removal of the tire which is then dunked in water to look for bubbles. Never use plugs for these except as a emergency measure. A good tire shop will break down the tire and patch from the inside then rebalance.

Carefully, inspect the TIRE VALVES and any extensions, adapters, extender hoses that might be attached to the VALVES.

If those valves are rubber, they can be a source of leaks and possible blowouts just by themselves. If the valves are rubber and anything more than a cap is attached, they become a time bomb. The weight worries the rubber till it fails.

Go to the Search Window, check Class C, type "metal valve" and read a couple of those threads. Custom brass one piece valves are the Gold Standard but others have been pleased with less expensive and less labor intensive solutions.

Interestingly, the least expensive custom valve kits are DUALLYVALVE sold at Camping World! Valve install requires breaking the tire bead down from the rim, and then the wheels should be balanced.

Find the Date Codes on the tires, as MrB noted above. It's the last four characters of a long string of letters and numbers containing "DOT" and the first two are production week. Last two are production year. So "2612" would be 26th week or June of 2012 making the tires coming up on four years old.

Hello:
Not an expert.... I have had several BLOWOUTS in early days of RV (bumper pulls), lots of damage done. Once I started to pay attention to tires, no more BLOWOUTS.

"Looking good" tires will kill someone.
How old are the tires? You must check and read info in small window on wall of each tire. There will be four numbers like this.... 0416 in an outline. Now windows contain more letters. See web site Tirerack.com for information.

Trying not to be "judgmental", the need to lean more (we all needed to do this) is coming thru...
Others should be here to help with gaining knowledge. Good luck and for all our safety, continue your questions,