Tire pressure and ride quality

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I notice that the ride quality on my 05 Explorer is so much better at 32lbs vs the factory 35lb spec. Running with 17" Bridgestone Dueler Alenza H/L's. I only do around 7K miles a year so tire wear and MPG's isn't really an issue tp me. I don't think running 32lbs is dangerous.
 
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Lower pressure causes the tire to heat up more while driving. This may lead to a blowout. Whether the difference between 35 and 32 cause problems in your case - I don't know, but given all the tire blowouts that Exploders experienced in the past, personally I wouldn't run then below factory spec.
 

Colt

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[LOL!] Actually it's a bit about the ride but the 32lbs less does make quite a difference on interior noise over bumps. The truck has a very quiet ride inside at 32 lbs. I believe the earlier problems with the Explorer had a 30lb tire pressure spec.
 
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Can't imagine having a serious problem because of 32psi! Memory isn't great, but I think Firestone tried to shift blame to Ford during last snafu because Ford door stickerd 26 or 28 psi. Also,,,you gotta remember those tires were FIRESTONES!! Bob
 

Colt

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quote:
Originally posted by alreadygone: Can't imagine having a serious problem because of 32psi! Memory isn't great, but I think Firestone tried to shift blame to Ford during last snafu because Ford door stickerd 26 or 28 psi. Also,,,you gotta remember those tires were FIRESTONES!! Bob
You're right about the 26lbs,Bob. "Ford has maintained since the controversy surfaced last year that the Firestone tires have been at fault for the rollover accidents. Since last fall, Bridgestone has maintained that Ford had long recommended a too-low tire pressure of 26 pounds per square inch that overburdened the tires, and that a design defect in the Explorer makes the vehicle too vulnerable to rollover during a tire failure.
 
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quote:
Originally posted by Colt: I believe the earlier problems with the Explorer had a 30lb tire pressure spec.
It was also a different model Exploroer, with different weight, and probably different tire size. You can't go by that.
 

Colt

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quote:
Originally posted by Quattro Pete:
quote:
Originally posted by Colt: I believe the earlier problems with the Explorer had a 30lb tire pressure spec.
It was also a different model Exploroer, with different weight, and probably different tire size. You can't go by that.

Good point but I don't think a 3lb difference would be that critical. I'd bet 90% of the tires on the road are off by 2-3 lbs or more.
 
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Just to make sure everyone has the facts. The tire size was P235/75R15 and the pressure spec from Ford was 26 psi. Firestone's argument was that at 26 psi the load capacity of the tire was exactly equal to the maximum vehicle design load. IMHO this is just poor engneering practice, especially considering that it was well know that folks don't pay attention to their inflation pressure. Ford has since gone to larger tires in all its trucks and SUV's (some cars and inivans as well!) So I guess they must agree, even if its a secret to be kept from the lawyers. But there's another reason not to use an inflation pressure lower that what is on the placard - vehicle handling. All vehicles are tested at the inflation pressure listed. Over and over again by lots of different people. If one were to lower the inflation pressure, the reaction of the tire (and therefore the vehicle) to steering input is slower. This might make the difference when avoiding the kid running into the street. It's these emergency situations where you have to trust the engineers who design and test these things. They get paid to put themselves in these situations and see how the vehicle reacts and if they find a problem - fix it (if they can!).
 

Colt

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quote:
Originally posted by CapriRacer: Just to make sure everyone has the facts. The tire size was P235/75R15 and the pressure spec from Ford was 26 psi. Firestone's argument was that at 26 psi the load capacity of the tire was exactly equal to the maximum vehicle design load. IMHO this is just poor engneering practice, especially considering that it was well know that folks don't pay attention to their inflation pressure. Ford has since gone to larger tires in all its trucks and SUV's (some cars and inivans as well!) So I guess they must agree, even if its a secret to be kept from the lawyers. But there's another reason not to use an inflation pressure lower that what is on the placard - vehicle handling. All vehicles are tested at the inflation pressure listed. Over and over again by lots of different people. If one were to lower the inflation pressure, the reaction of the tire (and therefore the vehicle) to steering input is slower. This might make the difference when avoiding the kid running into the street. It's these emergency situations where you have to trust the engineers who design and test these things. They get paid to put themselves in these situations and see how the vehicle reacts and if they find a problem - fix it (if they can!).
I feel I'm ok safety wise going 3lbs under. I check the pressure often and use nitrogen which holds 7-8 times longer than regular air. [Cheers!]
 
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tyre pressure and ride quality is a touchy subject. i feel confortable running most cars at 35lbs front and 30 rear. just depends on tyre squat and the load youre carrying. i use the manf recomendation as a minimum and go up from there. i have gone up to 44psi just for "testing" and such, but i feel 44 is too high for general use on a normal car. although it does give a nice fuel economy increase compared to manf specs on my rental car.
 
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26 psi ? What does a Ranger use with a moderate load ? 26 psi seems like a compromise, maybe for 'ride quality' so that the truck based Explorer doesn't ride like a truck. In both Taurus sedand we usually run 35 psi vs 32 psi per the door sticker, and even with that the last set of BFG Control TAs seemed like the shoulders wore more quickly, suggesting that more than 35 psi is warranted. The 3/4 ton truck is usually at 65/60 psi, sometimes at 70/65 psi for extended highway driving in warmer weather.
 

Colt

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quote:
Originally posted by hha27d: colt i think that you are ok at 32 but for the fun of it just use 33 - i heard somewhere that the absolute diff should never be more than 4 lbs less. Use 35 when fully loaded or at high speed for long times/distances
[Big Grin] I'm actually at 32.5 according to my digital gauge.Hoipe it's accurate. This is the gauge I want but it's pricey. Built in microprocessor for very accurate reading. Waekon Industries Tire Pressure Gauge Digital 2000 http://207.142.133.204/wm/21/Waet2000.jpg [Cheers!]
 
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quote:
Originally posted by Colt:
quote:
Originally posted by hha27d: colt i think that you are ok at 32 but for the fun of it just use 33 - i heard somewhere that the absolute diff should never be more than 4 lbs less. Use 35 when fully loaded or at high speed for long times/distances
[Big Grin] I'm actually at 32.5 according to my digital gauge.Hoipe it's accurate. This is the gauge I want but it's pricey. Built in microprocessor for very accurate reading. Waekon Industries Tire Pressure Gauge Digital 2000 http://207.142.133.204/wm/21/Waet2000.jpg [Cheers!]

i'm sure i got you beat on price and accuracy: http://www.longacreracing.com/catalog/item.asp?id=210&catid=8
 

Colt

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quote:
Originally posted by ChrisW:
quote:
Originally posted by Colt:
quote:
Originally posted by hha27d: colt i think that you are ok at 32 but for the fun of it just use 33 - i heard somewhere that the absolute diff should never be more than 4 lbs less. Use 35 when fully loaded or at high speed for long times/distances
[Big Grin] I'm actually at 32.5 according to my digital gauge.Hoipe it's accurate. This is the gauge I want but it's pricey. Built in microprocessor for very accurate reading. Waekon Industries Tire Pressure Gauge Digital 2000 http://207.142.133.204/wm/21/Waet2000.jpg [Cheers!]

i'm sure i got you beat on price and accuracy: http://www.longacreracing.com/catalog/item.asp?id=210&catid=8

$299! [freaknout] I feel $65 is pricey on the one I want but $299....
 
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I just want to caution everyone reading this thread about the dangers of using an inflation pressure lower than what is listed on the placard. The inflation pressure has a direct relationship with load capacity and overloaded tire failures can sometimes have tragic results. Inflation pressure also has a direct relationship with the speed capability of a tire. Inflation pressure also has a direct relationship on the operating temperature of a tire. And those are just the dangerous, tire failure related items. Just be aware that lower inflation pressure is going to hurt your fuel economy, hurt wet traction, hurt tire wear, hurt steering response, and, in my view the most important thing, moves you a few steps closer to a tire failure.
 
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That whole tire incident was all Fords fault. That truck was way too heavy for 26. The Jimmy is in the same category ran 32-35 lbs pressure. Any body I knew that had 32-35 lbs in their tires had no problems with their tires. You should be good with 32 just dont go crazy on the turns [Wink]
 
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quote:
Originally posted by Colt:
quote:
Originally posted by ChrisW:
quote:
Originally posted by Colt:
quote:
Originally posted by hha27d: colt i think that you are ok at 32 but for the fun of it just use 33 - i heard somewhere that the absolute diff should never be more than 4 lbs less. Use 35 when fully loaded or at high speed for long times/distances
[Big Grin] I'm actually at 32.5 according to my digital gauge.Hoipe it's accurate. This is the gauge I want but it's pricey. Built in microprocessor for very accurate reading. Waekon Industries Tire Pressure Gauge Digital 2000 http://207.142.133.204/wm/21/Waet2000.jpg [Cheers!]

i'm sure i got you beat on price and accuracy: http://www.longacreracing.com/catalog/item.asp?id=210&catid=8

$299! [freaknout] I feel $65 is pricey on the one I want but $299....

same guage that F1 cars use i'm sure, as well as nascar and just about any other major racing sanction.
 
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