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2018 Acura RDX - adding extra 1-2 psi to tires for cold weather

When putting air in tires do you always stop at the recommended PSI on the door or add a lb or 2 for cold weather? Living in Minnesota and Colorado for most of my life I have seen the low tire warning come on after a temp drop many times. Usually goes away. Seems to happen with all models. Just wonder if i am shortening the life with the extra air.

2-3 PSI usually will not hurt anything. I run my truck truck tires 3 PSI over, provides a more even wear pattern. The car goes by the OEM recommendation for ride quality.
Monitor your pressures on a weekly basis, before driving the car.

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Cold air is more dense (shrinks), which is why your tire pressure goes down. It’s normal. I put in what’s recommended, 32psi in my case, no matter what the temperature. However, if you’re expecting a drop in temperature it won’t hurt anything to add a little extra. I am concerned by the fact that your tire pressure warning triggers on a regular basis. My Corolla is nowhere near that sensitive.

I think the sensitivity may change on sensor manufactures or something. My 05 Town and Country alarms at 32 psi. Proper. Inflation is 35 psi. I get warnings at winter. I love that it is so sensitive. It keeps me on my toes. My 2020 Buick alarms at 28 psi. Tires supposed to be 35 psi.

… plus slightly better gas mileage and better handling under most conditions.
Like Purebred, I try to keep my tires inflated 2-3 psi over the vehicle mfr’s recommended pressures.

If the vehicle mfr, specifies different inflation pressures for the front and the rear, be sure to preserve that inflation differential when increasing the psi.

The OP needs to check pressure when the tires are cold. If inflating to correct PSI when tires are fully warmed up may drop enough to activate low pressure light when cold.

My Mustang specifies 32 PSI. I usually run 35 PSI. During the winter, it’ll drop to around 30/31 PSI. I’ll add enough to the tires to 32 PSI when the ambient temperature bottoms out for year. Usually when it starts getting warmer again the pressure will go back up to around 35 PSI by itself. Same thing with my F-150, only the specified tire pressure is 35 PSI, and I tend to keep it there.

Adding a couple extra PSI isn’t going to effect the tire’s longevity noticeably. If you could get 40k miles out a tire at 35 PSI, you’re going to get 40k miles out of the tire at 37 PSI.

Yeah it’s tough in Minnesota. I have yet to adjust the pressure in my RDX though. I just keep an eye on it in the winter. Problem is my garage is usually 40 or above so hard to get the proper pressure when outside. Last year the car sat out at about 10 below while at a movie and the pressure was down to about 24 psi on the way home. So a little over inflation in anticipation should be better than running at 25#, unless you want to check it outside in the cold, which is another problem. Putting air in at sub-zero temps can freeze up the valve and then you’ll have a leak.

I check tires once a month, first thing in the morning before driving, preferably before the sun hits it.
I note the current temp, estimate the coldest morning in the next month, and add 1 psi per 10 degrees F difference to the recommended pressure.
With my current cars’ ability to display tire pressures while driving I see they rise as much as 5 psi when warmed up.
So in a pinch if i had to add air on the road I’d inflate to 5 psi over to be close enough and safe.

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Don’t do that in Minnesota. Example: It’s 50 degrees in the garage and my tires are at 34#. In January it will get down to 10 below. That’s a 60 degree differential. I’m not going to pump my tires up to 90#. Unless you meant current outside temp which is 22. But that is still a 30# difference.

Whoops! I fixed it. 1 lb per 10 deg.
Actually, 1 lb per 12 deg F would be more accurate.

Perhaps I am of the less attentive driver, even with tpms I have not had to worry about tire pressure forever, but then I guess I am the lucky guy than may check oil level once every 6 months or wax a car every couple of years. So my 03 200k miles trailblazer got rearended last year, otherwise I would still be driving it, not saying do as I do.

I think you are very lucky your car doesn’t burn any appreciable amount of oil. Neither does mine but I still check it at least once a month.

Remember when gas stations had displays with bottles or earlier, cans of oil at the pump.

That did not change until the Japanese came in with engines that did not burn oil and forced Detroit to build better engines. That and the multitude of different weights made the gas stations stop the pump displays.

Now that I think of it the gas stations have mostly all disappeared, now you have convenience stores with pumps.

Consider the coldest weather you’re likely to get over the few weeks until you check them again and set the tires for that temperature.

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That’s not a problem. Just add 1 PSI for each 10 degrees difference.

Um, I don’t think I’m going to pump my tires up to 40 psi in anticipation of a January polar freeze. I’ll just check the TPMS from time to time.

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I do this every day. The shop temperature is 75 F, the outside morning temperature is 35 F, I need to add 4 PSI to the recommended tire pressure so that the tires are not under inflated while the vehicle is outside.

You can do what you want, but that doesn’t change the fact that it’s not “hard to get the proper pressure when outside”.

You pump your tires up every day? Or do you let some air out every day?

My employer makes me inflate tires for other people.