winter/summer tire pressure

i have 2017 civic hatchback exl. when i look at the user owner's manual i see tire pressure for 17inch wheels both front and rear to be 32psi. last week i took my car to service for oil change etc and i found out they added more air to the tires and they are now around 38-39psi. this made me question what i know about proper tire pressure for winter and summer. can anyone explain me what you set your air pressure and why? thanks

40 psi in both winter and summer (you need to add in winter and takeout for summer)
The higher psi = better mpgs
Lower psi = smoother ride (and I think handling)
I drive 100 miles a day for work and it's 95% highway, and a well up kept road. Don't need a more smooth ride or better handling so the increase in mpgs is nice.

Overinflated tires cause irregular wear of the tread. The middle of the tire wears out faster than them sides.

It's best to check the pressure once a month, to make sure the pressure is where Honda suggests so you have the best overall ride.

boston7686 said:

Overinflated tires cause irregular wear of the tread. The middle of the tire wears out faster than them sides.

It's best to check the pressure once a month, to make sure the pressure is where Honda suggests so you have the best overall ride.

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Agreed. The pressure should be the same, year round. I've learned that most shops will not bother to check the specifications for your car and will overinflated them.

boston7686 said:

Overinflated tires cause irregular wear of the tread. The middle of the tire wears out faster than them sides.

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Correct, but my last couple cars were also rated at 32 PSI and I kept them at 40. Once the tire was ready to be replaced, there was less than a mm difference between the middle and the outside tire depth.
That picture looks like the tire is rated for 30 and they have it at 60

the only problem i have is that honda service actually inflated them to 39psi. thats why i was questioning it

canerka said:

the only problem i have is that honda service actually inflated them to 39psi. thats why i was questioning it

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That's crazy, let them know next time that it happened last time, and see if they do it again. The shop I work at has auto inflators, so we set to pressure, and it does the rest.

I think 33-34 psi (cold) is typical. If you go 40 psi cold it's gonna be like 50 psi or higher when warm/hot. Seems too high to me.

canerka said:

this made me question what i know about proper tire pressure for winter and summer. can anyone explain me what you set your air pressure and why? thanks

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I set mine to what's on the door jamb sticker. Overinflate and it rides harsh, doesn't grip as well (important when you have to brake or steer hard), and reduces the contact patch. Underinflate and the tires ride ride on their shoulders and tend to roll over in corners.

I run them at the same pressure in winter or summer. I also ran my winter tires at the same pressure as my summer tires. What matters is, the air inside the tire is effectively a spring, supporting the shape of the tire. The pressure you measure is actually the difference between the pressure inside the tire and the ambient air pressure. Check it every few weeks, or when the seasons change, and reinflate if needed.

(I have purposely under- and over-inflated my tires before: underinflated the fronts for more grip at the dragstrip, and overinflated the rears to make the slide and add oversteer for auto-x. In both cases, I put them back to normal pressure before driving home)

BarracksSi said:

I set mine to what's on the door jamb sticker. Overinflate and it rides harsh, doesn't grip as well (important when you have to brake or steer hard), and reduces the contact patch. Underinflate and the tires ride ride on their shoulders and tend to roll over in corners.

I run them at the same pressure in winter or summer. I also ran my winter tires at the same pressure as my summer tires. What matters is, the air inside the tire is effectively a spring, supporting the shape of the tire. The pressure you measure is actually the difference between the pressure inside the tire and the ambient air pressure. Check it every few weeks, or when the seasons change, and reinflate if needed.

(I have purposely under- and over-inflated my tires before: underinflated the fronts for more grip at the dragstrip, and overinflated the rears to make the slide and add oversteer for auto-x. In both cases, I put them back to normal pressure before driving home)

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I agree with keeping the tires at the same PRESSURE from summer to winter, but the point is, the pressure in the tire varies with temperature.(ie winter - summer)
As it gets colder, the pressure reduces.

So, assuming there is no air loss
If the tires are inflated to say 35psi on a warm summer's day, (when the tires are at ambient air temperature -- ie have not been driven to increase their temperature) --- then, in the winter, when it is colder, of you measure the tire pressure, it will be lower than the 35psi that it read in the summer.
So, when the weather gets colder, you need to add air to the tire, to maintain the wanted 35psi.
Same does for the start of the summer, you need to let some air out to maintain the 35psi.

Unfortunately, he modern Honda Civic does NOT measure/indicate actual tire pressure , so the driver is not informed what the true, current air pressure is in their tires.
This means that it becomes more important to check the actual pressure at numerous times during a year.
If you want to keep your tires inflated with Nitrogen (and not just "AIR"), then it is not so easy to maintain the pressure yourself (at home), unless you have a nitrogen tank etc. (some added cost)

So keeping correct pressure becomes another reason to have to take your car to the Dealer, and all the fun and disaster that that can entail.

Note: Most Cosco locations will top up your Nitrogen filled tires for FREE, while you watch and make sure they do what you want, unlike the Dealer, who will take your car "out the back" where you are not permitted to see what they do (or don't do).

Conclusion: It might be worth considering adding after market tire pressure monitoring to your Civic, so you can more easily keep an eye on the tire pressures.
The External sensors seem to work well, are inexpensive, and can be fitted easily by the owner. (Might want to get wheels re-balanced after fitting).
Yes, the sensor battery has a limited lifetime, but typically the battery can be easily replaced.
One thing to watch for with the external sensors, is them becoming corroded to the valve stem thread. - should not be an issue if they are removed occasionally to adjust pressure, and the tread lightly coated with a corrosion inhibitor.. (I have not has any corrosion issues to date)

At the end of the day, I am a lot happier, and feel safer, knowing that I have checked and now what the tire pressures are, rather than relying on someone else, who may or may not do it right. After all, it's not their life on the line !!!

^^^^ Or you just be a responsible car owner and...

* have a pressure gauge in your glovebox
* eyeball check the tires occasionally before/after driving
* manually check the tires with your gauge about once a month and when the seasons change
* know where the gas stations are with free/inexpensive air pumps
* have a portable inflator at home just in case

Nitrogen is unnecessary for anyone who's not racing. The biggest benefit of a nitrogen fill is that there's less moisture inside the tire thanks to the process of extracting and storing nitrogen -- but that only affects how much the tire pressure changes due to big temperature swings (more moisture = more pressure change). The rest of the time, it's no big deal to use regular air.