After several years of RVing I have pretty much learned the ropes around our RV, and yet every so often something comes along that stumps me so thought I'd share this "stumper" with the forum and see what some of you think............. I pay strict attention to tire pressure after a serious blowout we experienced a couple of years ago. I know what the right cold tire pressure is for all six tires on our coach. However this last trip we took when I checked the pressures, I expected each tire to have dropped a few pounds from sitting for almost three months and boy did i get a surprise. My tire gauge (good one btw) and one other one I have as backup, both gave me readings of either spot on or slightly higher on each tire. This really threw me for a loop because I've never had any tire that didn't loose some pressure after sitting that long, let alone GAIN pressure. The morning I checked them was an average temp of about 65 degrees so it wasn't overly cold or hot. and neither were the few days prior to checking them. I called two tire shops and neither one could give me an answer as to why this could have occurred. IOne guy even laughed and said not to worry about it and just be thankful I didn't have to go thru airing them all up. Any guesse on this? I plan on checking them again today to see where they are at currently. I am not complaining one bit as that tells me the valves and stems must be really doing their job. We did have all new ones installed when we put the last set of tires on and the dealer where we got them said he was giving us the "best they had" and that the valve caps were some special type that were noted for sealing really good. They have a red color at the tip that supposedly means something to a tire shop, whatever that is. He told us but I have forgotten by now........... Any comments on how this "strange to me phenomenon" could have happened would be greatly appreciated................ Regards, Bankshot
The only logical explanation is that the ambient temperature was lower when you measured your tire pressure the first time. Or your flux capacitor needs to be recharged. (Guess who just watched Back to the Future again.)
Actually the temp when I last filled them was pretty close to what it when I checked them and found them all to high. But that would definitely have an effect on them gaining pressure for sure I would think. Oh, and as for the Flux Capacitor, I keep it fully charged all the time. One never knows when they might have to leave town in a hurry. Also, guess who just watched all three Back to the Future movies recently............??? One of my favorite movies too............. Thanks for the input Denali...........Regards, Bankshot
The only time this year when I needed to put air in my tires was my April & October trips. both trips tires were a couple # low and it was cold out. Checked before my other trips and pressures were good. as Denali mentioned temps play apart. Forgot to mention on a local summer trip this year I found the night before one of my tire pressures at "0"... found a big fat nail in the RV tire, changed the spare on it and went with my local trip with no spare tire. I was taking a chance but luckily I didn't get a visit from Murphy. I hear that camping world has a sale on those Flux Capacitors! Mike
When you took the tire pressure originally was you at the same location you are currently at? If not, a difference in altitude could have an impact, albeit slight. Equally, atmospheric pressure could make a difference if there was a high pressure system in your part of the country for one reading and perhaps a low pressure system for the other reading. Anyway, I'll leave your with flux in you capacitors while I go and fire up the warp drive on my truck.
To answer your question, yes, it was parked in the same spot as the prior check. I do move it back and forth a few feet every couple of weeks when it does sit for more than a month so as not to "flat spot" the tires, but other than that it stays where where we park it. As to the high/low pressure systems in the area during both times I can't say as that is something I never did think about, but you are correct, it could have an influence on the reading being as it was. I plan on checking them again this weekend to see where they are now after our return a couple of weeks ago. Will report my findings once I have done so. Thanks Hutch333id for your response and the heads up regarding the high/low pressure differences.................. Bankshot.
My coach tire pressures change by a pound or so as the sun moves around during the day hitting different tires from different angles even though the air temperature stays the same.
Another variance tire pressure maintenance is if you change manufacture or load ratings at tire replacement. I just put a set of 6 Sailuns load range H (14ply) with a capacity of 4080 lbs each @ 110 psi. Coach manufactures put the cheapest bare minimum rated tires and should be changed out ASAP. Here's a link showing the tires. Mine are just like these.
