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Check your new Ascent tire pressures! On cold measurements, one of my tires was at 43psi! The recommended was 33 psi.
 

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Check your new Ascent tire pressures! On cold measurements, one of my tires was at 43psi! The recommended was 33 psi.
That's a common thing to check for - and easy now, since the cars have individual tire pressure monitoring.

What happens is simple - the tires are inflated to a higher pressure before shipping from the plant. This is to help with bounce and sway while on the train car / car carrier. During the PDI (pre-delivery inspection), the service tech is supposed to correct the tire pressure. And sometimes they miss one - or all - of them. Not unique to the Ascent, or even Subaru. Happens at every dealership at some point.
 

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That's a common thing to check for - and easy now, since the cars have individual tire pressure monitoring.

What happens is simple - the tires are inflated to a higher pressure before shipping from the plant. This is to help with bounce and sway while on the train car / car carrier. During the PDI (pre-delivery inspection), the service tech is supposed to correct the tire pressure. And sometimes they miss one - or all - of them. Not unique to the Ascent, or even Subaru. Happens at every dealership at some point.
If they all have tire pressure sensors, shouldn't the sensor have picked up on the over-inflated pressure?
 

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Mine were over inflated too. I always check as I know they bump them up for shipping at the factory like Carl said. I know the pdi process is never 100%. Awesome that Subaru is finally showing each tires pressure on the dash! Now if they’d ditch the sensors completely that would be great!
 

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Mine were over inflated too. I always check as I know they bump them up for shipping at the factory like Carl said. I know the pdi process is never 100%. Awesome that Subaru is finally showing each tires pressure on the dash! Now if they’d ditch the sensors completely that would be great!
Although, personally, I usually go by the max psi on the tire. I do about 80% in the summer and 90% in the winter. These particular tires are max 50 psi, so the 41 psi on all my tires is right at 80%, so I left it.
 

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Although, personally, I usually go by the max psi on the tire. I do about 80% in the summer and 90% in the winter. These particular tires are max 50 psi, so the 41 psi on all my tires is right at 80%, so I left it.
Why would you run pressures at that high of a % of the max pressure for the tire year round?
 

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Got bit by this one too. I saw they were at 42 but stupidly assumed that's how it should be seeing as my dealer went over it with me. Then, on a 2-hour drive today, my TPMS keep acting squirrely giving me errors. So, I check the side sticker where it says 33. I was like, huh? No, something must be off here. Checked the manual and sure as heck, it's supposed to be 33. So, plus side is that I've loved how it's handled so far (817 miles!!!) Can't wait to see how it'll drive tomorrow with proper pressure! I'm assuming the TPMS will behave now ...

Rgashton - TPMS only started giving me an error today ... maybe it was the extended driving or heat getting the pressure up to 45. (Sidewall of tires has them rated up to 55 so it was never in danger)
 

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Why would you run pressures at that high of a % of the max pressure for the tire year round?
Because my family has owned tire shops all my life and that is what all the manufacturers recommend and it has worked well for me over the years. Very even tire wear and good gas mileage, so I stick with it.
 

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Although, personally, I usually go by the max psi on the tire. I do about 80% in the summer and 90% in the winter. These particular tires are max 50 psi, so the 41 psi on all my tires is right at 80%, so I left it.
I have to disagree and point out that to advise anyone to over-inflate tires contrary to the recommended pressures posted on the vehicle sticker is a liability issue. You can argue that the hazard of under inflation carries the greater hazard, but over inflation can create hazards as well. Over inflation decreases the contact patch on the road resulting in longer stopping distances, poor adhesion in wet weather and adverse handling. There is increased risk of shock damage and puncture, especially in wet weather; wet tires are more easily punctured. More common are tires that are under inflated which results in poor handling, tire wear and risk of blowout due to overheating. Under inflation is common with trucks, RVs and trailers because the tires fitted to those vehicles are often carrying close to their maximum load. Each tire has a maximum weight load and maximum tire pressure posted on the tire. The tire manufacturer provides a chart for each tire they make that shows the load range and the appropriate tire pressure for the weight load on that tire. On the Ascent, I would recommend that the owner acquires a quality tire pressure gauge and inflate the tires to the recommended tire pressure. Generally, if you anticipate carrying a heavier load such as bunch of adults, or a trip to the home improvement store for paving blocks, higher tire pressures are warranted. A full load of people could add half a ton more or less. If you want to nit-pick, you could look up the load range chart for the fitted tires on the Ascent and calculate the load on the tires. Inflate the tires to the higher recommended pressure. Not the usual thing for car owners, but anyone who drives a truck, RV or tows a trailer, will weigh the loaded vehicle at a public scale and adjust tire pressure according to weight. One good thing about the Ascent is the excellent ground clearance. That comes in handy when you come upon the carcass of a blown out tractor-trailer tire due to pressure loss and overheating; just drive over it if you aim correctly.
 

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If they all have tire pressure sensors, shouldn't the sensor have picked up on the over-inflated pressure?
It typically takes the individual sensors a couple of miles of use to be sending information to the car itself, so they won't pick it up at the dealership level.
 

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If they all have tire pressure sensors, shouldn't the sensor have picked up on the over-inflated pressure?
It typically takes the individual sensors a couple of miles of use to be sending information to the car itself, so they won't pick it up at the dealership level.
Ok I'll check ours out as well.

Am I hearing some of you guys correctly in saying you can check each tires pressure via the dash or infotainment display???

That would be much easier than fumbling around with a tire pressure gauge pen in a tight garage!
 

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If they all have tire pressure sensors, shouldn't the sensor have picked up on the over-inflated pressure?

The car arrives at the dealership lit up like a christmas tree. Pretty much every check engine light is on. They check and reset everything, then it takes a couple miles of driving to recalculate. When the recalculation happens the TPMS light comes back on, but often that is after the customer has taken delivery of the car.
 

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If they all have tire pressure sensors, shouldn't the sensor have picked up on the over-inflated pressure?

The car arrives at the dealership lit up like a christmas tree. Pretty much every check engine light is on. They check and reset everything, then it takes a couple miles of driving to recalculate. When the recalculation happens the TPMS light comes back on, but often that is after the customer has taken delivery of the car.
Saaaaayyy whaaaaat???!

Jason, don't scare us man! Why would all the dummy lights be lit up? Did they just tip the car off the train and onto the truck then pancake flipped it onto the dealership lot?? Lol.
 

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Saaaaayyy whaaaaat???!

Jason, don't scare us man! Why would all the dummy lights be lit up? Did they just tip the car off the train and onto the truck then pancake flipped it onto the dealership lot?? Lol.
No, that's normal. There's a fuse that the PDI guys have to pull from the shipping position and put it into the service position. All car manufacturers (or at least the ones that send to the lots near me) send their cars disabled this way. I think it's Audi's are shipped in limp mode, they can't hardly go more than 10 mph until they've gone through service.
 

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Saaaaayyy whaaaaat???!

Jason, don't scare us man! Why would all the dummy lights be lit up? Did they just tip the car off the train and onto the truck then pancake flipped it onto the dealership lot?? Lol.
No, that's normal. There's a fuse that the PDI guys have to pull from the shipping position and put it into the service position. All car manufacturers (or at least the ones that send to the lots near me) send their cars disabled this way. I think it's Audi's are shipped in limp mode, they can't hardly go more than 10 mph until they've gone through service.
That's interesting and actually pretty cool. I didn't know they did any of that.
 
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