Exceeding Maximum Tire PSI

[Glenn F.]

I need to make a 325 mile roadtrip with my heavily loaded minivan. Tire sidewall says 44 lbs PSI. Dare I go to 47? I’m just trying to reduce stress on the drivetrain.

Thank you,
Glenn F.

 

[Bob Bancroft]

I need to make a 325 mile roadtrip with my heavily loaded minivan. Tire sidewall says 44 lbs PSI. Dare I go to 47? I’m just trying to reduce stress on the drivetrain.

Thank you,
Glenn F.

I doubt 3 PSI will make much difference. A few different gauges will probably vary more than that!

 

[Mule Meat]

44 psi is max when the tire is cold.
Add a lot of weight and the heat generated by the tires will likely have you well above your 47 psi goal driving down the road... More likely closer to the danger zone.

Over inflated tires does not relieve stress on a drive line. If anything it's rougher on one. The bumps and bolts are transferred through the suspension system and into the drive line where as tires with the correct psi is able to absorb them.

 

[Glenn F.]

44 psi is max when the tire is cold.
Add a lot of weight and the heat generated by the tires will likely have you well above your 47 psi goal driving down the road... More likely closer to the danger zone.

Over inflated tires does not relieve stress on a drive line. If anything it's rougher on one. The bumps and bolts are transferred through the suspension system and into the drive line where as tires with the correct psi is able to absorb them.

Thank you for your input. My concern is the transmissions on these Dodge Grand Caravans are not known for their durability. Mine is working fine & I want to keep it that way. It seems to me a max inflated tire would pull/roll easier than a lesser one. ??

Glenn

 

[Phill Tibbetts]

I routinely run 4 or 5 psi over the tire inflation chart on the door, never have a problem but it does increase mpg a little.

 

[cjunrau]

Thank you for your input. My concern is the transmissions on these Dodge Grand Caravans are not known for their durability. Mine is working fine & I want to keep it that way. It seems to me a max inflated tire would pull/roll easier than a lesser one. ??

Glenn

Not sure what year dodge caravan you have. The trans are bullet proof if you just drive. What they can not and WILL not take is shifting from forward to reverse with the vehicle still in motion. There is a small pin that will shear if you try to rock it out of a snow drift or a mud hole. I ran 3 or 4 up to 250 thousand miles with no trans issues. 1998-2006 models. If you rock it out of a drift and it doesn't break, it will in less than 6 months if you put to much rock on it.

 

[Ray,IN]

Tire pressure beyond the sidewall maximum will make the tire more susceptible to bruising and damage from striking objects. Tire inflation will not have an effect on the transmission. Vehicle loading beyond the vehicles GVWR is what can damage a drivetrain.

 

[rustred]

I need to make a 325 mile roadtrip with my heavily loaded minivan. Tire sidewall says 44 lbs PSI. Dare I go to 47? I’m just trying to reduce stress on the drivetrain.

Thank you,
Glenn F.

no such thing. if it says 44 psi thats the max. and running at highway speed the psi will go up on its own from the speed and load. heavily loaded means slow down ! to prevent a blow out.

 

[MarkB_MI]

Three psi isn't going to make much difference, either to the tire or the van. But if you're already at 44 psi you're probably 8 to 10 psi over the recommended tire pressure for your VEHICLE. The tire pressure recommended by Chrysler is what they feel is the optimum pressure for handling, braking and tread life when the van is loaded to GVWR. If you need to go much over that you've probably exceeded max gross vehicle weight.

Look at the tires when the van is loaded and the tires are cold. Unless they have a huge bulge, they probably have enough air. And if they're still bulged at rated TIRE pressure, you'd better leave something at home. As I'm sure you know, radial tires have a slight bulge when properly inflated.

 

[Ericp351]

I routinely run 4 or 5 psi over the tire inflation chart on the door, never have a problem but it does increase mpg a little.

This ain't above the door/ glovebox placard. He needs to know about the TIRE MAX/ reasonable specs!! The car will advise based on-wait for it- the car. For example, better cars give recommendations based on tire press light or loaded. Jaguars give tire press based on over or under 100 mph,, et cetera. The people who made the tire "stamp" it with max press based on- again, wait for it, the TIRE. Your few pounds above "car spec." is probably well below the tire max, anyway.

 

[caterpillar guy]

Soft tires or squashing tires will blow before hard tires will. Especially these radial tires now days. The heat from running soft or squashing on the road will work the wires and cause them to blow out. I used to see it all the time on the road a vewhicle would go by me with a soft or squashy tire and I would see them down the road parked some place with the flat. Even semi tires or tractor tires will go eventually from running soft. Now the disagreements are sure to come. of course frequency and length of time run like that will alter all of this .

 

[BarnyardEngineering]

What nobody seems to have pointed out yet is that the pressure in the tire will increase as you drive, due to the tires warming from friction. 44PSI max sidewall pressure takes that into account. After you've been driving a while, the pressure will be at least 3-4 PSI higher.

There's absolutely no reason to exceed maximum pressure specified on the sidewall. You'd PROBABLY be fine doing it if your tires are in good shape, but it doesn't gain you anything.

 

[ss55]

I need to make a 325 mile roadtrip with my heavily loaded minivan. Tire sidewall says 44 lbs PSI. Dare I go to 47? I’m just trying to reduce stress on the drivetrain.

Thank you,
Glenn F.

What tire pressure does the door tag say? If it recommends 35 PSI and they are still squatting at 44 you are way overloaded. Consider renting a trailer with surge brakes to carry some of that extra weight. Check how close your axles are to bottoming out. Only an inch or two of clearance will pound at highway speeds on a rough road.

Gentle driving will do more to reduce stress on the drivetrain than high tire pressure. Manually downshifting out of overdrive when starting to climbing hills helps some.

 

[Brown David]

What nobody seems to have pointed out yet is that the pressure in the tire will increase as you drive, due to the tires warming from friction.

Been mentioned at least twice previously.

 

[Ray,IN]

The man who writes and maintains this website: https://www.rvtiresafety.net/ is a retired tire design engineer and tire forensics engineer. Anything you want to know about tires? He has written about the subject.

 

[buickanddeere]

Are we referring to max psi for max load ? On occasion somebody finds the max mounting pressure psi rating. Then incorrectly uaes those higher bead searing numbers for general use rolling down the highway .
As previously stated . Under inflation is the usual problem .

 

[Stephen Newell]

3lbs won't hurt anything. I don't think it would help anything either. If you over pressurize the tire enough to help it would damage the tire. If you overload it a lot you might better get 4 extra wheels and get bias tires for that purpose.

 

[rustred]

What nobody seems to have pointed out yet is that the pressure in the tire will increase as you drive, due to the tires warming from friction. 44PSI max sidewall pressure takes that into account. After you've been driving a while, the pressure will be at least 3-4 PSI higher.

There's absolutely no reason to exceed maximum pressure specified on the sidewall. You'd PROBABLY be fine doing it if your tires are in good shape, but it doesn't gain you anything.

i pointed that out yesterday.

 

[Geo-TH,In]

I need to make a 325 mile roadtrip with my heavily loaded minivan. Tire sidewall says 44 lbs PSI. Dare I go to 47? I’m just trying to reduce stress on the drivetrain.

Thank you,
Glenn F.

The tire pressure in my car will change 1 psi for every 10 degrees change in outside temp.
If I have 30 psi at zero degrees and drive to Florida where the air temp is 90 degrees my tire pressure will be 39 psi.
I think my tire pressure needs to average 36 - 37 psi. -
If I would put 37 psi at zero degrees the inside of my tire tread will wear out before the edges do.
I measure my tread depth and adjust air pressure to get an even wear pattern.
3 or 4 psi in no biggie deal. Good chance as you drive the sidewalls will flex and warm the air inside the tire and your pressure will go up.

 

[Mule Meat]

What nobody seems to have pointed out yet is that the pressure in the tire will increase as you drive, due to the tires warming from friction. 44PSI max sidewall pressure takes that into account. After you've been driving a while, the pressure will be at least 3-4 PSI higher.

Go back and read response #3.