Couple of psi lower tire pressure on the long road trips?

[zorobabel]

Originally Posted by Quattro Pete
Originally Posted by bullwinkle
More PSI=less sidewall flex, which is a leading cause of blowouts. .

Under-inflation, not over-inflation, is the leading cause of blowouts.


+1

 

[thescreensavers]

Image just an example

Higher tire pressure = better load carrying ability. You can go up to sidewall pressure cold that is listed on your tire.

So if you go on a trip with people and gear you you want to make make sure you have the correct pressure and are not underinflated.

 

[Pew]

Originally Posted by Quattro Pete
Higher pressures reduce heat buildup because there is a bit less sidewall flex.


This. Less pressure = more sidewall flex/contact patch = more friction = more heat. Part of the reason why track cars will increase/decrease tire pressure to adjust their car's grip (and contact patch.)

 

[Wolf359]

Originally Posted by RDY4WAR
44 psi is the max pressure on the sidewall. I've run 42 psi in these tires since new. They now have 41,000 miles on them and have no abnormal wear patterns. The vehicle rides smooth and handles well.

On that trip, I did check the tire pressure once on the way back after about a 4 hour straight run at 75 mph between fuel stops. I checked them while refueling and they they were all 43.0-43.5 psi so div>


I think you just got used to the ride feeling like rocks or truck tires, no give at all. What's the placard say on the car? I bet it's a bit lower. I would go a couple PSI's higher, but it sounds like yours is too high. I remember the tire store filling my tires up to 40 PSI once, the car rode like it had rocks for tires, you could feel every pothole. Dropped it down to 35 and the ride was much smoother. Now I keep an eye on the pressure after taking it in for service.

 

[maxdustington]

Originally Posted by kschachn
Maybe his sledge hammer method of determining tire pressure reflects his skill in other areas.
It's not the first time I've heard of that method of determining tire pressure, you are the idiot: https://www.amazon.com/RoadPro-RPTT-1-Thumper-19-Inches-Assorted/dp/B001JT5CFY

 

[RDY4WAR]

Originally Posted by Wolf359
Originally Posted by RDY4WAR
44 psi is the max pressure on the sidewall. I've run 42 psi in these tires since new. They now have 41,000 miles on them and have no abnormal wear patterns. The vehicle rides smooth and handles well.

On that trip, I did check the tire pressure once on the way back after about a 4 hour straight run at 75 mph between fuel stops. I checked them while refueling and they they were all 43.0-43.5 psi so div>


I think you just got used to the ride feeling like rocks or truck tires, no give at all. What's the placard say on the car? I bet it's a bit lower. I would go a couple PSI's higher, but it sounds like yours is too high. I remember the tire store filling my tires up to 40 PSI once, the car rode like it had rocks for tires, you could feel every pothole. Dropped it down to 35 and the ride was much smoother. Now I keep an eye on the pressure after taking it in for service.


My wife drives it from time to time and she prefers it at the higher pressure. "It actually turns now when I move the steering wheel."

The placard on the door says 35 psi, but it felt like a boat at that pressure.

 

[kschachn]

Originally Posted by maxdustington
Originally Posted by kschachn
Maybe his sledge hammer method of determining tire pressure reflects his skill in other areas.
It's not the first time I've heard of that method of determining tire pressure, you are the idiot: https://www.amazon.com/RoadPro-RPTT-1-Thumper-19-Inches-Assorted/dp/B001JT5CFY

If you say so. But in my world, anyone that trusts their sledge hammer skills more than a calibrated tire gauge is the idiot.

The other thing I wondered about was that the trucker said "you will never get an accurate reading on a gauge with hot tires". How is it different than when using the sledge hammer? Does the sledge hammer method give an accurate reading on hot tires whereas the gauge does not?

 

[Wolf359]

Originally Posted by kschachn
Originally Posted by maxdustington
Originally Posted by kschachn
Maybe his sledge hammer method of determining tire pressure reflects his skill in other areas.
It's not the first time I've heard of that method of determining tire pressure, you are the idiot: https://www.amazon.com/RoadPro-RPTT-1-Thumper-19-Inches-Assorted/dp/B001JT5CFY

If you say so. But in my world, anyone that trusts their sledge hammer skills more than a calibrated tire gauge is the idiot.

The other thing I wondered about was that the trucker said "you will never get an accurate reading on a gauge with hot tires". How is it different than when using the sledge hammer? Does the sledge hammer method give an accurate reading on hot tires whereas the gauge does not?


There may be many methods out there but some of them can be considered idiotic even if you end up at the same result. I had a plumber once who used to check for gas leaks by lighting a flame and running it around the joints. I thought he was nuts but he claimed that it was a valid method as the pipes are only at .5 psi so if there's a leak, you would only see a slight puff of flame and you'd just blow it out. I would just prefer checking for the bubbles method and also in terms of tires, using a pressure gauge.

 

[toneydoc]

Just follow what the door placard says
The tires have been tested on that vehicle at that PSI
No reason to under or over inflate them

 

[The Critic]

Originally Posted by kschachn
Originally Posted by maxdustington
Originally Posted by kschachn
Maybe his sledge hammer method of determining tire pressure reflects his skill in other areas.
It's not the first time I've heard of that method of determining tire pressure, you are the idiot: https://www.amazon.com/RoadPro-RPTT-1-Thumper-19-Inches-Assorted/dp/B001JT5CFY

If you say so. But in my world, anyone that trusts their sledge hammer skills more than a calibrated tire gauge is the idiot.

The other thing I wondered about was that the trucker said "you will never get an accurate reading on a gauge with hot tires". How is it different than when using the sledge hammer? Does the sledge hammer method give an accurate reading on hot tires whereas the gauge does not?

I think the RoadPro is used to determine if you have a stupid-low tire; it is not intended to be an accurate method of measurement.

I have no idea why anyone would expect a sledgehammer to be a remotely accurate means of determining appropriate inflation. Crazy.

 

[dubber09]

If some of you recall Ford Explorers were blowing tires en masse due to incorrect and low PSI listed on door jam placard.
I bet those tire that blew up were low on pressure and possibly quite old and cracked.

 

[Wolf359]

Originally Posted by dubber09
If some of you recall Ford Exploders were blowing tires en masse due to incorrect and low PSI listed on door jam placard.
I bet those tire that blew up were low on pressure and possibly quite old and cracked.


They were low so it would ride less like a truck. But it was set at 26 psi. Both parties were partly to blame. There were Goodyear tires on Ford Exploders that didn't explode but the Firestone ones did.

 

[gfh77665]

I air up my tires usually 2-3 PSI over normal for long highway trips! Keep 'em cool!

 

[Danno]

Originally Posted by kschachn
Originally Posted by RDY4WAR
I have a good friend up in Canada who drives a truck delivering liquid nitrogen all over North America. He said they never want to see the rear tires go below 80 psi as that is a danger zone for a blowout. The sidewall flexes too much which generates internal friction and warping which can cause the tire to blowout. He said he aims for 95 psi in rear tires and 110 psi in front tires with a range of 85-100 psi for rear and 100-115 psi for front. However, he said you will never get an accurate reading on a gauge with hot tires. He carries a sledgehammer in the cab and when he stops, he bangs the tires with the hammer. If the tire is low on pressure, it'll make a dull sound. If it's overinflated, it'll make a ping-like sound. He will then verify it with a gauge and/or let a little out and bang again.

He said the most calls his company gets from drivers with blown tires is people going from sea level to high elevation. As the ambient pressure decreases, tire pressure increases (relatively), and increases the chance of over-inflation and a blowout if the pressure isn't dropped accordingly.

If the 3 or so PSI difference between a high and a lower altitude is causing tire failure then there's something else going on.

Maybe his sledge hammer method of determining tire pressure reflects his skill in other areas.

He may be doing it that way, but its not the way it is trained by tire manufacturers. Been to truck trade shows where we were given the hammer and no way to tell if the tire had 80 psi or 100 psi, and the 80 psi is basically a flat tire for trucking purposes.

 

[Luftmasse]

I usually buy tires can go up to 51 psi, and I pump it up from 40-42 psi cold.

 

[dubber09]

Much higher than recommended PSI isn't good either, car/truck would ride like on wooden wheel and not so great for suspension or bearings.
I run +2psi on Forte and +4 front and +2 rear on Sportage and only due to soft tires sidewalls causing a little bulge.

 

[JohnnyJohnson]

Lowering tire pressure all you're doing is giving away MPG.

 

[circuitsmith]

Re MPG vs PSI: there's a point of diminishing returns.
Given the car makers CAFE concerns, I'd think there's little to be gained by going over the placard.

 

[SwampSurvivor]

The last trip I took I had the tires inflated to 80PSI*. My Subaru, however, seems to have a really low recommended pressure. 29R,30F. I usually run 33,34.



*I was towing a 7000 pound trailer 500 miles.

 

[litesong]

Originally Posted by RDY4WAR
I..... the most calls his company gets from drivers with blown tires is people going from sea level to high elevation. As the ambient pressure decreases, tire pressure increases (relatively), and increases the chance of over-inflation and a blowout if the pressure isn't dropped accordingly.
Oh, thank you. Since I live near sea level. I've never thought of that before. Within the last 5 years, I've started inflating my tires to 4-5 PSI over normal (with very nice results). I'll remember your post, if I drive to mountain pass elevations to 7000 to 14,000 feet. I'm a featherfooter tho, so my top speeds of 60-65MPH(not 80+MPH), should also be a factor to avoid over-inflated tires.