Probably about 5 or 6 months ago I pumped my (16") tires up to about 36 psi. Yesterday all 4 were showing just a bit over 31. Pumped them up to 35/36 but was surprised they had lost that much pressure.

A friend said he was't surprised, and said that he checks his tires every 3 months and expects to see pressures to drop like mine did.

How often does everyone check pressure?

 

Clear you are not using nitrogen in you tires? What happens is that if they are cold at 36psi the heat from friction of tires and road will increase the pressure by 4to 7psi.
Also in winter the opposite happens to me. When it gets really cold (sub zero in Celsius) the tires can deflate and if you aggressive drive in the first couple of minutes they can leak around the rims because the pressure is so low. This happens especially if you run low below 30 psi in your tires.

 

I've found it depends on the tires more than anything else. Michelin Pilot Sport 2s were the least 'leaky' tires I've ever had. I've made it a habit to check every time I do 'work' on a car, whether an oil change, detailing, track inspection (duh), etc. which ends up being every 2-3mos. Of course with TPMs, it's a lot easier.

 

Tires loose 1 psi/month with general use.

They also change 1 psi for every 10degF of temp change.

I use nitrogen, then again I get it for free at work.

Much more stable.

 

Not surprising at all.

The rule of thumb I was taught growing up was to check at every fill up.

I don't do it that often anymore, but I'll check them once every month or so, then fill them up with my air compressor as needed.

 

I've never understood the hoodwink of paying extra for nitrogen when the atmosphere is 78% N2 to begin with. Tire pressure varies dramatically with seasonal temp. changes. If you find a dramatic change in pressure occuring without the help of a nail, you're not checking them often enough.

 

I only use the stuff that's 78% nitrogen, the same stuff I breathe. I think the temperatures when I have typically checked the tires are roughly the same -- no extremes here in Fla. Interesting point about losing pressure from aggressive driving.

 

I check once a month and add as needed. If it seems to be a lot of pressure lost, I will increase checking frequency to 2 weeks, 1 week, etc. And obviously look for leaks if it has become a problem.

 

Good idea, I'll check a lot more often than I used to. It sure is easy in the MINI -- my wife's 2014 Mazda CX-5 doesn't offer the same convenience.

 

The nitrogen tire thing has been the subject of many threads. What I learned is that the fact that nitro tires stay more even is that there's no moisture in the nitro cans. So if you fill tires with humid air there can be way more difference in pressures at different temps. Mine rarely need air. I'm in AZ "it's a dry heat"!

 

i think aluminum rims leak more than the old steel rims.

 

I check mine every 3 months at which point I usually need to add 5 -7 psi.

Nitrogen-fill is a gimmick as those still need to be checked. Nitrogen-filled tires don't lose air quite as fast, but they still "leak".
Greg