Can you run on low tire pressure?

[tatkin]

Sent: 2/22/2007

How low can you go ?    Tire pressure I mean. The only reason I ask is I have seen reference to a better ride if you have radial tires. I don't have radial tires . Am I asking for trouble if I run the fronts at say 50 lbs . I think I have them at like 80 lbs right now ...

[Oz]

Sent: 2/22/2007


That 80 lbs is your max load pressure.  There's all kinds of variables involved, but without the complete scientific explanation I'm sure you will soon receive, under standard load, 65psi front and 60 rear is what I run on.

- Sob

[bluebird]

Sent: 2/22/2007


I would run the tire pressure that is on the tire. That is the recommended pressure. Low air = heat, heat = tire failure. Even on a properly inflated tire, heat is a problem on older tires. Plus fuel millage will suffer.

[Elandan2]

Sent: 2/23/2007


Try looking up the tires on the manufacturers website.  They usually have a load chart which shows the air pressure required to carry a certain load.  If you know the weights of your rig at each wheel or dual, you can adjust the pressure accordingly.  Remember to add 5 psi. or so for safety.  Having the tires inflated to the maximum will certainly make for a rough ride.   Rick

[Oz]

Sent: 2/23/2007


Using the "Message Search" and the key words Tire Pressure, you would find all this additional of info:


- Sob

[Oz]

Sent: 2/23/2007


What you will find is that the pressure you can run on depends entirely on the type, manufacturer, size, recommended pressure, load rating of your tires and actual load on your tires according to the manufacturer.  You said they were bias, but the rest of the info is needed as well.

I run between 60 & 65 lbs on mine because I safely can.  You may not be able to on yours.  To ride on max pressure if it's not needed is just creating a ride like having rocks for tires.  I did this too for the longest time until I got a better idea of what it all meant.

You would need to provide the information about your tires I mentioned above in order to reference the correct pressure for your load.

- Sob

[drummertom]

Sent: 2/25/2007


I have bias ply. My first trip out, my winnie was hard to handle. Someone behind me pulled up beside me and told my one of my rear tires was very low. Just for grins, I decided to check them all. I pumped them all up to recommended pressure and it was like day and night in the way it handled. My vote is for recommended pressure. The ride may be stiffer but the handling improvement outweighs that (IMHO).
Tom

[Oz]

Sent: 2/25/2007


Note that the vote is highly in line with bias ply tires.  They are designed with stiff sidewalls and are a totally different animal than radials with the bulging sidewalls.  A bias tire isn't something I'd fool around with lower than mfg recommended inflation.

- Sob

[tatkin]

Sent: 2/26/2007


I think my idea for a better ride has been deflated ...

[denisondc]

Sent: 2/28/2007

   My front tires have a "sidewall max pressure" when used as singles, of about 90 psi.  I usually run about 70 or 75 psi.  The rear tires I run at 65 psi, though the sidewall marking calls for a max pressure of about 75 when used as duallies.  I run less than the "sidewall max" because the tires are carrying 20%-25% less than the maximum weight.   With these pressures they all run at the same temperature on the highway.   Even in the hottest weather and on black pavement at 60 mph,  my tires will run cooler than they would be if left lying flat in the sun.   All of the tires are bias ply, tube type, and 4 of the 6 of them were 'used' tires that I bought on ebay to get the split rims they came on.
     I have never run them at the maximum pressure on the sidewall, so I don't know how the ride would feel.    Mine rides well enough that I don't care to spend time trying to get it better.
        We had pulled into a rest area once, and looking back I could see one front tire was definitely low - low enough for the rim to be about half as far from the pavement as on the properly inflated tires.  I think it had 25 psi in it, and was quite warm.  I don't know how long it had been under inflated, since I hand yet felt a difference.    The (slow) leak was from around the valve stem to tube connection; an inner tube gone bad due to age and sunlight.  No damage to the tire.  I put on the spare myself, and we continued on our trip.   This is the only time my Winnie has had a tire problem underway, in over 50,000 miles.    Hooray for bias ply tube type tires, and split rim wheels.       !!!
     When the winnie has been sitting over the winter, the tire pressures all seem to drop about 10 psi - and I inflate them back to my favorite pressures before going anywhere.  My procedure is to check the tire pressures 2 weeks before a trip, and set them as listed above.  Then the morning before we are going to leave I check the pressures again.   This is to find any slow-leaker's! - and give me a day to take care of the situation.

[ClydesdaleKevin]

Sent: 3/2/2007 5:39 AM


In the Ark, because we lived in it, we always ran the tires close to max...the Ark was LOADED with all of our stuff, so we compensated for the weight...75 in front, 70 in back.

Running with pressures too low can do a few bad things:  First, it can be dangerous...you don't want a blowout!  Second, it can prematurely wear out your tires.  And finally, it will make our already crappy gas mileage suffer even further.

Kev