Yet another tire pressure question
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Yet another tire pressure question
I see alot of the pressures everyone is running while towing, but my question is, because your maximum pressure will vary depending upon your specific tire, how close are you to the maximum pressure of your tire? Thanks.
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The best way to determine tire pressure is by using a pyrometer. Measure the tire temps on the outside, middle and inside part of your tread immediately after doing a run. If the temp is higher in the middle then the sides, you have too much pressure. Likewise if the temp is higher on the sides then in the middle, you don't have enough pressure. Ideally, you want equal temps across the tire. Also if the temp is higher on the inside tread then the outside, you have too much negative camber. If your temp is higher on outside than the inside, you have too much positive camber. Tire pyrometers run app. $100, but over the life of your driving, it will prolong the life of your tires and will extract the most performance from them.
Spaggs
Spaggs
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Joined: Oct 2005
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From: Florida
The sticker on the drivers door showing tire pressues per the load charts WILL carry the full gross axle weights.
However those are pretty low pressures in most cases.
While from a pure LOAD standpoint as long as one isn't overloading their axles...the door sticker value for front and rear IS sufficient...you have to remember that the tires are a HUGE PART of the suspension.
When hauling or towing heavy...tire pressues can be an easy **** to turn to tune in on a better setup.
My suggestion to folks is always start AT the pressures on the door sticker and work UP from there in 5psi increments if handling needs tweaked.
Many advise to simply go to the maximum listed on the tires...and in many cases this causes its own issues...I found out first hand that too much pressure really made my towing handling very squirely (sp?)...so I backed off the psi's and have an incredibly stable handling setup.
I found that making the tires too hard had a negative result...but your results may vary.
Joe.
However those are pretty low pressures in most cases.
While from a pure LOAD standpoint as long as one isn't overloading their axles...the door sticker value for front and rear IS sufficient...you have to remember that the tires are a HUGE PART of the suspension.
When hauling or towing heavy...tire pressues can be an easy **** to turn to tune in on a better setup.
My suggestion to folks is always start AT the pressures on the door sticker and work UP from there in 5psi increments if handling needs tweaked.
Many advise to simply go to the maximum listed on the tires...and in many cases this causes its own issues...I found out first hand that too much pressure really made my towing handling very squirely (sp?)...so I backed off the psi's and have an incredibly stable handling setup.
I found that making the tires too hard had a negative result...but your results may vary.
Joe.
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Good info, but I dont have the original tires on the Ex. I have Hankook (yuck) 285's that are load range D's with a maximum pressure of 65 lbs. I'm just wondering what would be a good starting point for this experiment to find the towing "sweet spot." I basically am just trying to find out if most people are at or near the max on the air pressure.
Hotshot
Joined: Oct 2005
Posts: 12,237
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From: Florida
With D range tires...for towing...given that they have an inherently softer sidewall to begin with...
I'd start at 55psi rear and front to see what you think. Load wise...as long as you aren't over the GAWR on the door jamb...you are fine at 55...but if you need some more side wall stiffness...up the rears first to 60 and then 65 while keeping the front at 55...then if you are still needing more...up the front to 60 and finally 65 if you haven't hit on a good combo before then...
Also run the trailer tires to maximum on the sidewalls...
But that is simply some advice...
Good luck,
joe.
I'd start at 55psi rear and front to see what you think. Load wise...as long as you aren't over the GAWR on the door jamb...you are fine at 55...but if you need some more side wall stiffness...up the rears first to 60 and then 65 while keeping the front at 55...then if you are still needing more...up the front to 60 and finally 65 if you haven't hit on a good combo before then...
Also run the trailer tires to maximum on the sidewalls...
But that is simply some advice...
Good luck,
joe.
Junior User
Joined: Feb 2004
Posts: 55
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From: Akron, OH
I've been messing with my tire pressure.
Ran at the door pressure first. was getting 12.5-13 mpg and the front would wonder on the freeway.
Went to 60 front and 65 rear and the wonder was a touch better at best but the milage went up to about 14.5ish.
So now I am trying the sidewall pressure of 80psi. Getting roughly 15 mpg highway. City still sucks and around 12 at best. The wonder is better but it still wonders.
So I'm going to leave it at 80 for a bit and see how it goes. Think I need to do an alignment to cure the wondering on the freeway. Drives fine around the city.
Ran at the door pressure first. was getting 12.5-13 mpg and the front would wonder on the freeway.
Went to 60 front and 65 rear and the wonder was a touch better at best but the milage went up to about 14.5ish.
So now I am trying the sidewall pressure of 80psi. Getting roughly 15 mpg highway. City still sucks and around 12 at best. The wonder is better but it still wonders.
So I'm going to leave it at 80 for a bit and see how it goes. Think I need to do an alignment to cure the wondering on the freeway. Drives fine around the city.
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