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Wrong tire pressure

why don’t service stations put proper inflation in tires?

I donno, why?
For that answer you will have to ask them.
What exactly did they do to you?

What kind of improper inflation did you receive?

Do you live in California where facilities are required to adjust your air pressure to manufacturer specifications and document it on the repair ticket?

laziness- most places around here put them at 32 unless you tell them otherwise, and sometimes even then.

They never put in manufacturer’s specs listed on the driver’s door jamb. I had new tires installed and they put 36 psi instead of 29 man. specs.

Did you bring this to their attention? Maybe their inflator gauge is wrong.

I put my tires 2 lbs below the maximum inflation pressure ON THE TIRE.

“I put my tires 2 lbs below the maximum inflation pressure ON THE TIRE.”

Doing this is not really a good idea. It reduces the tire’s footprint on the road, which will compromise handling and the vehicle’s ability to hold the road. This will result in unpredictable handling and a greater risk for an accident, which would be catastrophic at triple digit speeds, Robert. Additionally, once you’ve been on the highway for a few minutes, the temperature of the tire will increase the pressure beyond the maximum. Go with what’s printed on the door jamb tag or in the owner’s manual. As a less important note, overinflated tires will make the vehicle ride like garbage. Twice recently I have purchased wheels and tires from a fellow who overinflates tires, and within a block of driving I can tell they are overinflated. Some people do this in an effort to save gas, but it will not make an appreciable difference. If you see a difference from doing this, it’s not real. It’s a product of the brain damage caused by bouncing your head off the roof of the car due to the tires having too much pressure in them.

Why do you do this?

If you were to ask in this forum: “What is the proper inflation pressure?” you will get a variety of answers - we’ve already had one incorrect answer! That is part of the problem.

Other parts of the problem? Carring little about customer service. Speed (it takes time to reset the pressure). And a whole lot of “worrying about me and not so much about my job”.

[i] I put my tires 2 lbs below the maximum inflation pressure ON THE TIRE.[/i] 

That is NOT a recommended pressure.  It is there to tell you that IF the recommended pressure is more than what is on the sidewall, then the tyres are not safe for your car.  If you don't believe me, maybe you can believe the guys who put that number on the tyres:

From the Goodyear site.

Tire Inflation
Proper tire inflation is a key ingredient in driving safety and long tire life. It is wise to check your tire’s inflation at least once a month with an accurate tire pressure gauge. Continuous loss of inflation pressure is an indication of a possible tire/wheel assembly problem; consult your tire professional immediately if you encounter this situation. Be sure to check the pressure while the tires are cold, and have not been used recently. If you drive even a mile this will cause your tire pressure to increase and give you an inaccurate reading.

Check Your Air Pressure
Keep your tires properly inflated and you could improve gas mileage by more than $1.50 every time you fill your tank. The recommended tire pressure for your vehicle is located on a sticker inside your driver-side door or noted in your owner’s manual.
You might also try the US Department of transportation.
They say:
You can find the correct tire pressure for your tow vehicle in the owner?s manual or on the tire information placard.

I put my tires 2 lbs below the maximum inflation pressure ON THE TIRE.

I suggest you learn a little about tire inflation and how temperature can drastically effect tire pressure.

If you set the pressure to 2lbs BELOW max when it’s 50 degrees outside… and then the temperatures rise to say 75…the tire pressure is now ABOVE the max rating. Also as you drive this generates heat which also will raise tire pressure.

And lets not forget about it can drastically reduce your control of the vehicle. AND…give you uneven wear on the treads in the middle of the tire.

This is NOT a good idea…

Most mfr recommended pressures are too low so people don’t complain about ride quality, and most people don’t check often enough, hence the tires will be even lower than they so-called spec.

Under inflation is far more common than over-inflation. Most of today’s tires can handle far more pressure than in the past. Perhaps 36 is a bit high. In over 40 years, I think I’ve seen evidence of over inflation in ONE set of tires.

2lbs below the “Max” pressure is just asking for trouble. Check the tire placard on your vehicle for the proper pressure. That’s the only way to go.

A lot of tire shops will inflate the tires a few pounds over the recommended pressure. When I ask them why they do this they usually say it’s to keep the new tires seated on the rims. Always check your tire pressure after any maintenance. That goes for any fluids in your vehicle as well. It’s “your” vehicle.

The “Maximum Cold Inflation Pressure” accounts for the fact that the tire will heat up and the pressure will go higher. Robert could inflate them to the maximum pressure and the tires would still be fine, even after they heated up.
The tires would be fine, but Robert would not. He needs to inflate to whatever the pressure spec on the vehicle says to get the best handling, and clearly he needs the best possible handling he can get.

It would appear that whatever pressure is put in tires it will be wrong. But it’s always 5:00 somewhere. And a broken clock is exactly correct twice a day.

“…A lot of tire shops will inflate the tires a few pounds over the recommended pressure…”

Believe it or not, new tires grow enough in the first 24 hours that +2 psi immediately after mounting becomes right on 24 hours later. The guys at those shops were probably told WHAT to do, and they made up the WHY based on their limited understanding of what actually takes place.

This is a really bad and dangerous idea. If you fill them that way cold they’re probably beyond the maximum safe pressure when you come off the highway, especially at the high speeds you travel. Even if they’re not, they’re still much more prone to catastrophic failure at maximum hardness. And your traction is seriously compromised from what it would be if you had them at the proper pressure.

Did you check the tire pressure cold or after you had driven home from the shop. Makes a difference, you want it checked cold.

+1, though 29 to 36 is probably a bit more than what would normally occur(?)