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View Full Version : Tire PRESSURE!



Francesco Rizzo
12/17/2004, 08:47 AM
I visited my dealership and they expressed the concern of using correct tire pressure due to the extream sensitivity of the TOD system. I run mine at 29 psi and when I brought it in it was at 35... they gave me this big lecture. I've had to chang the transfer case, which luck for me was covered under warrenty... I keep reading people having higher pressure... is this ok, I keep mine at the 29...

autox-racer
12/17/2004, 08:54 AM
if the circumference is the same on all 4 tires then what is the big deal? tire pressure can effect traction but still that should have no effect on the TOD other than when you loose traction.

marximus
12/17/2004, 09:40 AM
what preesure did they tell u to keep the tires at?
29?

t2p
12/17/2004, 10:53 AM
I'm not an automotive engineer ....... but I did stay at a Holiday Inn once .......
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the 29 psi rating will provide optimum comfort ........
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plus ..... the 29 psi is a *cold* measurement .... 29 psi cold may mean 32 psi when the tire is up to operating temp ....
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also, the 29 psi recommendation may actually lessen the chance of rollover ....... higher psi may actually lead to increased traction and therefore increase the chance of rollover in the event of a emergency manuever (think Ford Explorer - Ford recommended low psi to reduce the chance of rollover - but Firestone countered the low psi could contribute to tire failure ...)
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I can not remember the last time I kept tires as low as 29 psi - the tires wore unevenly (on the outsides) and the handling (cornering) sufferred. In addition, cupping on vehicles with 4wd was more likely to occur.
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Tone
12/17/2004, 03:26 PM
LOWER pressure will contribute to a rollover! The tire will compress and can pop off the bead in an evasive manuever - think how your front tires squeal and understeer when they are low on air. What was essentially happening with the Explore was they specified a lower pressure for COMFORT and not handling and the tires essentially overheated and blew. Also when a rear tire blows it is far more difficult to recover from than if a front one goes. 29 is the recommended comfort pressure for stock tires ONLY - follow the tire manufacturers ratings and the closer to to max listed on the tire, the better your mileage and typically the tire wear. It is also MUCH safer on long, higher speed travel to be at a higher pressure so the tire does not flex and heat up excessively as the Explorer Firestone's did.

Heraclid
12/17/2004, 04:10 PM
I had run every rallycross at 40 psi until last time and had never popped a bead when so many other folks did. Last time I didn't pay attention and ran with lower pressure. Sure enough, while I didn't have a tire come off the rim, I did get debris in the bead and developed slow leaks in two tires and they had to be cleaned up and remounted.

I don't get comfort from lower tire pressure at all. It gets worse, not better. I get a considerable improvement in handling and comfort by keeping 'em pumped up to at least 40 psi. I'm running BFG Mud Terrain light truck-type tires with a 50 psi max cold pressure rating, but my experience is that they do feel a bit less sure-footed at the high end so I don't go over 45 psi cold.

OZ VX
12/18/2004, 01:30 PM
40 sounds good, thats what I always run mine at. Get better fuel economy too, with less road resistance.