The question was "Do you inflate your tires to what it says on the tire, or what it says on the vehicle?"
And we couldn't believe how many of the answers were dead wrong!
No wonder there are so many blowouts and people with tire problems.
All tires have maximum ratings imprinted on the sidewall of the tire for both weight and pressure. Note that these are MAXIMUMS.
So, you can put the maximum pressure in the tire, and that in itself will not damage anything. However it can seriously affect that handling of the vehicle and the wear on the tire.
But the problem is, the tire doesn't know which type of vehicle it will end up on!
And so every vehicle manufacturer will have a notice somewhere on the vehicle that states the recommended tire pressure for that vehicle. Engineers and designers spend millions of dollars coming up with the optimum tire pressure for that specific vehicle, taking into account safety, handling, tire wear and probably a bunch of other variables. This is what you need to pay attention to.
From an Airstream travel trailer.
Note that the photo above also includes a statement about the weight of the cargo. Your RV has maximum weight limits that work in conjunction with a properly inflated tire. But because the manufacturer doesn't know what you will be taking with you, on most of these labels the recommended inflation pressure is for a vehicle that is loaded to the maximum stated weight limits.
Most people have NEVER weighed their RV. Yes, you should weigh it with it loaded the way you normally would travel with your RV... people included. It might hold less than you think and therefor you are overloaded.
Incorrect tire pressure or being overloaded could result in this!
And more likely than not, when this happens it is due to a combination of the two.
I'm a bit of a stickler when it comes to tire pressure, so I check mine regularly on both the little blue car, and the motorhome. Hopefully this article will give you the impetus to check your tires regularly too!
--------------------------------------------------------------------------------------------------------------------------
If you've been wanting to try an electric induction cooktop, here's your chance. This is a new product, so not much review history, but the price is right. Most single burner induction cooktops sell for between $50 and $85...
What amazes me is how so many so-called tire "professionals" routinely inflate tires to the sidewall pressure, totally ignoring the vehicle placard.
ReplyDeleteYes, I know. Eve when I dealt with a local, large franchise when I was in the auto body business, I always had to double check the pressure when I had tire work done. It's often because it's low paid kids working in their first automotive job at the tire shop. Same thing with oil change kids. That's why I always change my own oil!
DeleteGood info. It is amazing to me how many people do not even check the tire pressure regularly. I once helped a motorhome owner next to me at a rally with airing up his tires. They were at the 50 percent point. I asked him when was the last time he checked them. He said 4..5 years ago!
ReplyDeleteYikes, 4.5 years without checking the pressure, that is scary! I hope that after taking with you the motorhome owner will now be checking it regularly.
DeleteI'm anal about my tire pressures. I've seen a truck and a bus blow a tire while driving down a highway, as well as the results of several RV's that blew tires. Don't want that to happen to my well loved motorhome.
ReplyDeleteYou sound just like Kevin! Nope, we don't want anything to happen to our motorhome or ourselves either because having a blowout could result in all kinds of scenarios.
DeleteA lot of fifth wheels come with a 4500 pound axles, the sticker that you're talking about is usually for a six ply,
ReplyDeleteTire out the door at the manufacture
The sticker does not address the upgrade to 8 or 10 ply tire assuming that your rims are in line with the eight and 10 ply tire the Numbers on the side wall should be the determining factor
Using the numbers on the vehicle door could be a difference of 25 to 35+ pounds creating again and unsafe factor
Correct. The sticker assumes that you will always use the type and size of tire that the manufacturer recommends. If you "upgrade" or use something different, you had better guess correctly.
DeleteVERY well said, Kevin. Many RVers blindly "upgrade" to higher load range tires without realizing that the higher PSI means less rubber on the road, and thus reduced braking performance. Not to mention likely exceeding one or more weight ratings if the intent is to "safely" carry more cargo.
DeleteDoug I need to differ with you a 235 /85/ 16 comes in 6 ply 8 ply and 10 ply and 14 ply
DeleteBoth the 8 an 10 ply recommend 80 psi
The tread that touches the road surface is the same on all these ply tires
If inflated to the manufactured specifications
You forgot the ply rating represents the < side wall > not the tread portion
"Recommend 80 psi"... ? Or maximum 80 psi... ?
DeleteMister Ed, I didn't forget anything. Road contact area is not a function of the number of plies nor even the tire size. It is simply the load the tire is carrying (in pounds) divided by the pressure (in psi). Increase the psi, you reduce the road contact area and thus braking performance, simple as that.
DeleteThe manufacturer placard always specifies a particular load range: LRD=8 ply, LRE=10 ply, etc. So using a different load range and/or a different psi is just wrong. Why is that so hard to understand?
That was Maximum PSI 80
DeleteDoug you feel that you're right that's OK
I feel that I am right that's OK Pissing match is over
You and Sherman just go together! Great photo and great information about tire pressure. Thanks for sharing your knowledge.
ReplyDeleteThanks Lori, we think we do too! We sure are missing him at the moment.
DeleteWow so much to know about fire inflation. I use my truck manual to set the tire pressure for normal city streets and for hauling loads. I usually increase pressure when I know I'm going to be hauling a load...maximum load is 1500 lbs. Otherwise my tire pressure is set at normal city street travel. I once had to deflate the tires while driving on sandy road to keep from getting stuck. I've seen some of my relatives put a load in the truck bed to give it traction on icy roads but I've never done that...probably unsafe is what I think. I do see the tire stats on the side walls but I usually use my truck manual which makes me a little nervous because I don't want to blow a front tire at high speed due to pressure being set wrong.
ReplyDeletePS: so in your photo example the tire max is 1477 but the airstream max is 1700. Does that mean that tire would not be a good fit for the airstream?
DeleteThe tire above was just an example... it wasn't meant to go with the Airstream... but yes, you are correct.
DeleteGood advice on tire pressure, We never move our coach without checking the tire pressures. Have had our coach weighed a few times as well as the individual wheel weights And yes we go by the vehicle manufacturer recommendations.
ReplyDeleteThanks George! If we were meant to go with the maximum pressure on the tire sidewall then why would the manufacturer's go to the trouble of putting up their little table of weights and proper tire pressure on your RV vehicle, unfortunately many people don't follow this rule, glad to see you aren't one of those. :-)
DeleteThe last time I got new tyres on the front of my Winnebago it felt as if I was riding on steel wheels..Horrible!..i checked and the kids at the shop had inflated to what it said on the side of the tires...I dropped it 20-30# and the ride is nice and the tires are wearing swell!
ReplyDeleteUpriver
We have also had the same experience when we get new tires put on our motorhome or the car. Kevin always has to double check the pressure before we leave and usually has to let out some of the air to bring the pressure down to what is recommended by the sticker/plate on our motorhome.
DeleteHi guys, I enjoy reading your journal as my wife and i prepare for retirement and our life on the road and in the air. This is my second time responding to an issue on your pages because this tire thing is in my field as an aviation inspector. Theres only two reasons that tires explore, one is no matter what the tire pressure is if the tire is dry roitted. Those little cracks in the side wall or tread base are killers. Secondly is an under inflated tire as little as 10 lbs on these high pressure truck-rv tires. An under inflated tire will build up heat and the rubber compound has to work harder at holding the load up, this causes the tire to blow. We have never had an accident with over inflated tires it is always under inflated. You should use your vehicle manufactures recommendations on tire inflation, then if the vehicle is poor handling or poor fuel milage due to load vs tire inflation then air up the tire presssure but never to max ! If your tires are to weak due to the load ratio (your overladed rv ) then change to a heavier ply tire (like go from a 4 ply tire to a 8 ply tire). But make sure the loaded rv is not over loading your suspension. Most truck stops and grain companies have truck scales so you can weigh in, and get ready for a supprise, j
ReplyDeleteOur rv is a 2007 Freightliner M2 Class 7 with 330 hp and a 33,000 lb load rating using 14 ply tires at 100 psi tire pressure that is checked each time before we role out.
Yep, you're exactly right John. I think many RV'ers have never been to a scale with their rig, and many are overloaded and know it so they don't want to go to a scale!
Delete