One of the things my dad taught me is that before long, hot trips, I should deflate my tires slightly. We live in the desert, so tires get very hot. Supposedly, deflating them slightly, by 2-3psi, helps relieve the extra pressure built up during these long drives (+10 hrs). Is this good advice? Or should I keep the pressure at the same pressure? While we're at it, should I have 35psi with a cold tire, or a warm one? Thanks.
2006-08-07 11:27:05 · 7 answers · asked by Robert 1 in Cars & Transportation ➔ Safety
I think your question is more complicated than what the owners manual may say.
First, the door or glovebox sticker WILL give you the recommended pressure for the tires that came on the car as original equippment. You may have changed brands, size etc.
All pressure ratings are done COLD. IE: before driving the car.
The sidewall air pressure number on the tire is the MAXIMUM cold pressure for that tire. This number may be much higher than the car's sticker.
The sidewall also has one other very important set of ratings on it, especially for your question about desert driving in the summer. It's called the UTQG rating. The first letter is for treadwear, the second for traction, and the third is for temperature rating. They all are A,B, or C ratings, with A the best and C the worst. The sidewall also has a load rating from 71 (761 lb rating) to 110 (2337 lb rating), with each higher number giving a small increase in load capacity . You can also be at or near the max load for the rating of the tire.
Of course the load of the car makes a big difference too. If you are travelling across a desert, on a hot summer day, going high speed, with a full load of passengers and cargo/luggage, this would be the worst case for build up of heat in the tires.
I think in a hypothetical scenario where you have a C temp rated tire, and say the car sticker is close to the sidewall pressure rating, there isn't as much leeway for inflating to the car specs, but not exceeding the tire maximum pressure.
Tires can increase in pressure about 1 lb per 10 degrees, and can easily in the hot, loaded, high speed, desert conditon increase by 10 lbs pressure.
Now, lowering the air pressure usually results in MORE heat in a tire due to increased friction and is not recommended, in this case where you may be near the max load rating, on a C temp tire, which has a max PSI shown on the sidewall which is also close to the car recommendation. If so, I would drop the pressure 1 or 2 lbs PSI knowing it will soon increase towards the max pressure. I would NEVER increase the pressure above the sticker PSI in this circumstance.
At the least, you can look at the sticker and the sidewall for the ratings and for once KNOW what kind of tire rating you have. Paying extra attention to the load, and temperature rating.
2006-08-08 07:46:38 · answer #1 · answered by rkfire 3 · 1⤊ 0⤋
No, actually that will increase the chance of a blowout! Sorry, but your Dad was completely wrong on that one.
Read your owner's manual and it will explain it all quite clearly. If you are going to drive a long high-speed trip, you actually want to INCREASE the tire pressure in most cases by 3 - 5 PSI!
There's a label on the door jamb of most vehicles that tells you the correct tire pressures. Some vehicles put that label on the inside of the glove compartment door or on the inside of the fuel filler door.
You always measure the tire pressure while the tires are cold. Cold is defined as having been driven for less than one mile after standing for 4 hours or more. If you check the pressure when the tires are hot the reading will often be higher than normal. NEVER lower the pressure of a hot tire! That's a sure plan for a blowout!
2006-08-07 11:58:21 · answer #2 · answered by Bostonian In MO 7 · 0⤊ 0⤋
Thats and old wives tale.... the safest thing you can do before a long trip or any trip at highway speed, is to inspect your tires for any cracks or bubbles and inflate/deflate to the proper psi... and never let the tread on your front tires get below 4/32 depth.
2006-08-08 06:38:35 · answer #3 · answered by monie99701 4 · 0⤊ 0⤋
No you'll get bad gas mil age. Keep them at the recommended pressure. Just don't run over sharp objects
2006-08-07 11:47:45 · answer #4 · answered by anne 2 · 0⤊ 0⤋
I don't think that having the proper pressure is going to cause them to burst. I do know that decreasing the amount of pressure below the recommended amount will cause premature wear on your tread.
2006-08-07 11:32:16 · answer #5 · answered by Skot M 2 · 0⤊ 0⤋
It wouldn't hurt to let air out. Your tires are going to heat up and replace that air anyway. It is best to replace old tires, because old tires tend to burst under extreme heat. Get new tires and you shoul be fine.
2006-08-10 15:26:29 · answer #6 · answered by sunflowerlizard 6 · 0⤊ 0⤋
nope, will kill your gas milage!
2006-08-07 21:54:39 · answer #7 · answered by WMR30 3 · 0⤊ 0⤋