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Proud G6 Owner
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Discussion Starter #1
Hi everyone,

I've been seeking what the correct tire pressure should be for my car. The tag on the door has faded so badly, I can't even read it.

I have a 2006 G6 GT with 225/50/R17 Tires which I just had a new set installed last month.

If anybody can forward me how much pressure each correctly inflated tire is (in psi)

Thanks.
 

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it says 30psi front/rear on mine... but isnt it supposed to be higher psi for front coz of engine weight??
 

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[ZeR0]pocketaces2012
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it says 30psi front/rear on mine... but isnt it supposed to be higher psi for front coz of engine weight??
Mine says 30 psi aswell. Eveytime I take my car into the dealership or into my garage I always get heck for "over inflating " past 30 psi.
 

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Proud G6 Owner
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Mine says 30 psi aswell. Eveytime I take my car into the dealership or into my garage I always get heck for "over inflating " past 30 psi.
Thanks guys. When I had my tires replaced, each tires was inflted to 40 psi which I thought was a little too high. But 30 seems a little low especially with all the bumps and exposed potholes we have here in Toronto. For the time being, I've kept it at 35 psi but I may need to call around to figure out which tire pressure should give me the best fuel efficiency.

I was also hearing about inflating the tires with Nitrogen. Has anybody had this done and is it worth it?
 

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Varsity Squad
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You will find that almost all GM cars call for 30 psi front and rear regardless of tire size, even if you change sizes. I have noticed some center wear so I typically will run about 28 psi. As for the most fuel efficent, well max psi will give the most fuel efficent, but worst ride quality. Nitrogen is a relatively new concept, but keeps the tire at a lower operating temp helping to wear a little bit longer, you will lose less of it due to temp changes, but it is a PITA trying to find a place that has it if you need to adjust your pressures. If someone dosent have it you need to let all your air out of the tires before adding the "regular" air.
 

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Moderator Member Thingy
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The three main things about nitrogen in the tires is:
- Less seeps through the tire rubbers due to the larger molecule size
- Fluxuations in operating temperature inside the tire stays consistent so the PSI stays the same.
- Less moisture in the tire which prevents rotting of the tire. Pure nitrogen is dry, while air compressors can still compress the moisture from atmosphere.

I always keep my tires around 30 psi (stock tire size). When I got my tires put on though, they inflated it to 37-40 psi. I asked why and they said that it was probably temperature fluctuation. HA!
 

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When I got my tires put on though, they inflated it to 37-40 psi. I asked why and they said that it was probably temperature fluctuation. HA!
They have to over inflate to seat the bead, but must have been too lazy to set it to the correct psi. The temp change is def some BS they were trying to feed you, since it couldn't have taken more than an hour to mount them all. It is hard to find a shop you can rely on!
 

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Well 30psi for the rears are okay, but through fronts should be more. Concerned more about the fronts than the rear.

I am not sure what other people get as thread wear for the fronts. But it looks like more wear on the sides of the tire than the center of the tires.
 

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I run my tires around 35-36 psi. The ride is a bit harder but I get better MPG. And its not over inflated to the point of bursting or bad tread wear. Always been around 36 and wear is perfect still.
Plus it stiffens up the tires to the point of increased handling. Which is nice
 

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Well 30psi for the rears are okay, but through fronts should be more. Concerned more about the fronts than the rear.

I am not sure what other people get as thread wear for the fronts. But it looks like more wear on the sides of the tire than the center of the tires.
Yes the edges will wear more in the front tires. It's designed that way.
Increasing the tire pressure will upset handling, increase under-steer, and stiffen the ride. Stick with factory recommended tire pressure for best overall performance.
 

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Yes the edges will wear more in the front tires. It's designed that way.
Increasing the tire pressure will upset handling, increase under-steer, and stiffen the ride. Stick with factory recommended tire pressure for best overall performance.
It's DESIGNED that way??? that the lamest thing I've ever heard. Designed for tires to wear like there are under-inflated..

I am going to raise my PSI to 32-33. I rather have my tires last longer than 25,000kms!
 

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I run mine hard at the advice of a friend who owns and runs a shop and regularly races his car. I have to run 40 when on a banked track. Otherwise my sidewalls take a beating.
 

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It's DESIGNED that way??? that the lamest thing I've ever heard. Designed for tires to wear like there are under-inflated..

I am going to raise my PSI to 32-33. I rather have my tires last longer than 25,000kms!
Yes it's lame but true. Again, they are designed to wear like they are under-inflated. There are a lot of engineering involved in determining the optimal tire pressure. Being a FWD drive car, the G6 is very nose-heavy and have a high tendency to under-steer. If you increase the front tire pressure, you will reduce the front traction. Physics doesn't change for appearance sake. Even if you pump your front tires to 40 psi, they will still look under-inflated due to the car's unbalanced F/R weight distribution, and it will handle very poorly. There is a reason why GM set the tire pressure to 30 psi all around, not 33 front 30 rear. If you want longer tread life, follow proper procedures and rotate your tires regularly instead of playing around with tire pressure.
 

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Well it is upto 32PSI all around now.. I always rotote tire frequently which has caused premature wear on the outside walls. With our cold climate, we loose air quite a bit here. we'll see how it goes.
 

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Tire pressures are listed for the OEM tires. Manufacturers such as GoodYear, Michelin, Perilli and so on, use different compounds and the like in tires for certain manufacturers. These tires will drive and feel differently then if you were to purchase 4 new ones from a local tire centre. It's minimal, but characteristic changes such as air pressure, tread depth and design might vary slightly. It's becoming more commonplace among all brands to increase fuel economy. A certain tire is picked during the engineering process of the car, from the wind tunnel to the test driving track, it's put through its paces and the car company sends their specs to the tire manufacturer once production of that vehicle gets the green light.

All wheels from steel to aluminum, are able to handle well over 750psi air pressure before their integrity becomes compromised. It takes a lot of air pressure to bend steel/aluminum.

If a tire on the sidewall states to run it at say 40psi, then run it at 40psi, as that is the pressure the TIRE was designed to be driven at for optimal traction, fuel economy, and overall performance.

If the sticker on the car door says "30 or 32psi" that is for the OEM tires ONLY. If you keep buying the OEM tires, then it's best to adhere to GM's recommended air pressures to get the best value out of the tires. My OEM Conti's were normally at 35/32 (front/rear) and the door sticker stated 34/34psi (front/rear). The tires were rated at 35psi.

I have General Tire UHP tires and they're listed at 50psi. I fill them up to 45-48psi. Some manufacturers state on the tire that it's "50psi cold" meaning they can handle 5psi more once warm without causing harm or lowering economy/performance. Most lower profile tires are built with a higher air pressure in mind so (it was already mentioned here) to increase sidewall stiffness, among other things. If a tire is rated at 50psi and you want to run it at 30psi, it's dangerous. Plain and simple. It will work, but you'll lose handing, braking performance, mileage, and you will be lucky to see half of the life those tires were meant to provide you. It's a simple no, no, no, no, and READ the sidewall. Within +/- air pressure of 3psi is best to gain the maximum benefits your tires can give you.

You will be surprised how poorly your car brakes when the tires are not inflated to the air pressure listed on the sidewall. I dare you to find an empty parking lot and try it. It could come down to either hitting the guy who cut you off, or not hitting him and stopping short. What you have to ask yourself is what you would prefer to happen in that situation.

Front tires should always hold a slightly higher air pressure over the rear tires to offset the additional frontal mass of FWD vehicles. This helps lower vehicle roll in corners. Most owners don't care about handling, performance, or even mileage. They just want to get from A to B without any sort of fun mixed in. In that case, it doesn't really matter if the front/rear tire pressure is different or not, as they won't 'feel' it.

Hopefully this clears things up a bit.


It's DESIGNED that way??? that the lamest thing I've ever heard. Designed for tires to wear like there are under-inflated..

I am going to raise my PSI to 32-33. I rather have my tires last longer than 25,000kms!
I concur! Tires are not designed to wear in any other way then level and true. Wear on the outer edge of a tire indicates alignment woes or failing front end parts. This is why tire rotations are a good thing to do at least every oil change or within 8K miles. Even sooner with lower profile tires or tires with a very low tread wear rating.
 

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Great info 360ci!
Thanks!

I'm no expert by any means, but after reading 14 or so posts and NO one asked or stated to check the tire pressure on the sidewall, I had to jump in!

I have a landscape business and used to drag race (modified but not funny car class), and tires can make or break a race. Your track car might have a value of $1000, but you'll have $3000 worth of rubber on the vehicle. A bit less if you don't run super wide racing slick tires. Proper tire inflation is just as important as a quick rubber warm up before you take off down the track.

My trucks & cars are over maintained so I know I can get into any one of my vehicles RIGHT NOW and drive it down to Florida and back (2750miles) knowing it shouldn't give me any issues except for unforeseen failures (fuel pump, alternator, etc). I've only ever had one tire wear unevenly over the hundred and some I've bought, thanks to me forgetting to replace a tie rod end in my Durango. oops.
 
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