I have the Yokohama Geolander G033 P215/70R16tires on my 08 ES. About a week after I bought the car I went out one morning and checked the tire pressure and was suprised to see all 4 tires at 38 psi.Mitsu'srecommendationis 32 psi.

Iwent back to thedealer and spoke with a service advisor and he recommended I keep them at 38 psi to improve mileage and treadwear. I now have 2900 miles on my outtie, have takentwo 500 mile trips andI'm pleased with the mpg and handling at 38 psi.

I'm curious to know what other outtie owners here keep their tire pressure at..

 

Your service advisor is completely out to lunch. While you may seen some marginal gains in mpg, you are causing the following:

1.Faster wear of your tires
2. More potential for blowout caused by added stress to tires
3. Decreased contact patch on the ground which means braking is longer under emergency situations

Just for point 1 above, the savings in fuel will end up eaten and more when replacing your tires more frequently.

You should report your service advisor to Mitsubishi. Think about it, if it were a sensible thing to do, the sticker on your inside door would recommend inflating to 38 psi. The engineers are by far more intelligent than a service advisor.

 

Yes, I agree with dekodan. Even though higher tire PSI may get you maybe a very little better on gas mileage, it can cause you on the long run. When I was working at my previous auto shop, customers bring in car with their tire pressure over 40 psi. Yes, a little better gas mileage, but cause faster wear in your tires, and it will affect your handling in emergency (skidding, losing control, ect.). So 38 psi is not the way to go. From 30-32 is fine for the Outlander.

 

I'm curious about the point of faster tire wear. Maybe I'm totally wrong on this, but I thought heat wasone of theenemys for tire wear, and doesn't running higher pressure in your tires reduce heat buildup in the tire? I realize the type of surface you are driving on (ie rough pavement) has a lot to do with tire wear, but all other things being equal doesn't a cooler tire reduce wear?

 

Maybe I am wrong, but I think that it will wear the tire faster because the higher pressure for tires, the less surface is contact to the ground. 32 PSI is the best pressure because it evenly speard the weight of the vehicle into the entire surface of the tire. However, for higher pressure, less surface is being contact, so the only surface that is actually touching the ground (center of tire) will have to support more weight, therefore the center of the tire will wear a lot faster, because is carrying more weight than usual, and the edge of the surface will have lots of thread still. If center threads of the tire is no good, then the whole tire is useless, and is time for new tires!

Remember for you all that have high PSI in your tires, always consider that -> High Tire Pressure = Less Tire Surface = Losing Control of Vehicle = DANGOURS!

 

The reason why he said 38psi was to avoid having the "low tire pressure light" on. When you have the tires set at 32psi they are more likly to set that annoying light b/c most car owners dont check their tires as often as they should.

Imo your not gonna notice a big change in mpg's andtire wear @38 psi, they only thing is that it might ride just a bit harder. Thats it. I think the rest of you guys are over reacting a bit much.

 

you probably checked your pressure after the car was already moving. best way to do it is cold temps. when the car has not been running for a while in a shade.
cause 32psi will become 36-38psi after driving for a while.
i ran 38psi on the oem tires and upsized to 235/70/ R16 and am now running 36psi nitrogen.

 

dekodan, do you design tires, or familiar with the physics involved in tires?

You are on target with your first & third statement. More specifically, too high of pressure will typically cause the center to wear out faster than the shoulder. The faster center wear is due to less shoulder in contact with the road for a given loading condition. The higher pressure will decrease the contact patch. There is an optimum pressure which is typically what the placard value states.

Increasing the pressure from 32 to 38psi will not necessarily increase the likelihood of what you call a blow out. In most cases, potholes or some other impact damage causes it to lose air. It is not so simple as lowering pressure to avoid this is. It can actually be the wrong thing to do in many cases. Tires are very robust and will not just pop if you inflate them to their max rated inflation pressure.

Bottom line.....Go with vehicle placard for your pressures for OE size tires. When you plus size, you may need to adjust pressures to compensate for less air volume in the tires, but that is a case by case type of thing to be recommended by tire experts (not typically anyone employed at a dealership).

 

i suggest running 35psi and not 32psi. you may gain 1-2mpg.
not gonna ruin your tires or cause an accident like what some people seem to imply.
but make sure it is 35psi cold.

 

Let me clarify a couple of points. While the 38 psi is over inflating the tire based on mitsubishi's recommendation of 32 psi, the max psi rating for this tire (as found on the side of the tire) is 44 psi, so in that regards the tire is not over inflated.

As far as the tire being inflated to the point where the contact patch is smaller, I can not tell any visible difference in the contact patch at 38 psi, or 32 psi, and there is no center bulge that I can see at 38 psi. But again thats just my observation with the naked eye.