Are my tires over inflated?

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I went to air up the tires on both of our vehicles yesterday. Our new Jetta's tires were all around 32 PSI, the door sticker says 36. I don't have a compressor at home so I used one at the Shell station we fill up at. The machine was malfunctioning so it set the PSI at 42. I checked the max inflation on the stock tires and it says they are rated to 52 PSI. I understand I can just let some air out, but for MPG / handling I wouldn't mind them a LITTLE higher than the recommended 36 PSI. Is 42 PSI too high or should I just leave it?
 
I'd air down but if the ride quality is fine with you go for it. Watch the center tread for excessive wear.

Fyi, I use this VIAIR for our vehicles:
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Screenshot_20200826-070426.webp
 
With sketchy pumps, overfill them and then lower at home in the morning to your desired pressure.

Before I had my Ryobi tire pump, I'd just go to Discount a Tire and have them fill them up to 40 psi (not all that accurate IMO with their gauge and having hot tires), then the next morning I'd lower to 36 and call it good.

I like setting my tires to 2 psi over placard for some buffer room.
 
Under inflation is bad. Over inflation is a non issue if kept under maximum pressure per sidewall. I would run them as high as comfortable a few pounds under max. In your case about 46 psi. I wouldn't worry about wearing out the center of the tires. They aren't bias plies and the manufacture wouldn't warranty a tire that would prematurely wear out all the way up its max pressure. There are going to be applications for this tire that require 44 psi I bet. Portable compressor? Meh.....you need this at home.
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Under inflation is bad. Over inflation is a non issue if kept under maximum pressure per sidewall. I would run them as high as comfortable a few pounds under max. In your case about 46 psi. I wouldn't worry about wearing out the center of the tires. They aren't bias plies and the manufacture wouldn't warranty a tire that would prematurely wear out all the way up its max pressure. There are going to be applications for this tire that require 44 psi I bet. Portable compressor? Meh.....you need this at home.
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As a compressor technician, I have to wonder how that air filter change works?
 
As a compressor technician, I have to wonder how that air filter change works?
It doesn't look to be bolted to the ground so prolly just tilts/turns it a bit.

As for the tires, usually running a few psi over the placard is fine, unless maybe a very small//light car, then I'd stay at what it says. Unless you are loading up a vehicle the placard is usually best all around plus a few psi I've seen imho...
 
Overinflation can change the contact patch, but not with just a few psi over. I have heard of tires changing handling characteristics dramatically but usually it takes several psi, not 3, for the effects to be noticed by most (now if you're racing and can actually measure lap times or such, then perhaps 1psi matters).

I often like a few extra psi to firm up the ride, but wound up running the placard in our Camry's as the effect wasn't large and I seemed to get the best and most even wear when not over-full. Other vehicles have preferred a bit more than sticker so as to get best wear. YMMV.
 
As a compressor technician, I have to wonder how that air filter change works?
I twist it for filter service. I bought the compressor at a farm store that was closing out more than a decade ago. I went ahead and bought a case of the Quincip oil and a dozen air filters. I changed filters often the first few years to stay in warranty but now only change periodically with use. I am out of filters and down to one quart of oil. The compressor doesn't see much use any more. Battery powered tools have pretty much supplanted it.
 
These aren’t slicks where a small pressure change can change handling.
I usually run a chalk test and then put it 2 PSI over the result.
 
The challenge is finding an accurate gauge. I have 3 different auto-parts-store-grade gauges at home, and they all read different. One of them reads exactly the same as the TPMS on my Canyon, but I've read those units aren't accurate at all. What do you trust when no two gauges read the same?
 
As a compressor technician, I have to wonder how that air filter change works?
That was cute ( and a good catch)

As a former one, its simple. Remove the rack and replace when you change the filter. ( doesn't look Queezy blue so my guess is that's an after market)
 
Couple years ago I tested a bunch of pencil gauges against each other, threw out the ones that were wildly different. And realized that this was a junky solution so I bought a digital gauge for $10 or whatever off Amazon. Which could be just as wrong as anything else, but I'd only know if I bothered to compare it against anything. Only issue I found is that I cannot store it in the garage, when the temps drop below 50F or so it seems to no longer work properly.
 
with all the roundabouts here in North Indy, I always have mine 5 psi higher than door sticker. Actually BMW recommends higher pressures for higher speeds/loads
 
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