Discount Tire tech claims I had no TPMS Sensor inside stock Ford wheels

[robvas]

I don’t see how low pressure could decrease circumference thereby increasing wheel speed. The radius decreases, but it is not a circle and the circumference is simply stretched out further on the road and is exactly the same as when fully inflated. It seems to me unless the tire is slipping on the rim the wheel must turn at exactly the same speed regardless of tire pressure.

https://www.hondainfocenter.com/Sha...ndirect-Tire-Pressure-Monitoring-System-TPMS/

Sponsored

 

[krisk]

https://www.hondainfocenter.com/Sha...ndirect-Tire-Pressure-Monitoring-System-TPMS/

Interesting. I’ll have to read up on how those work. From a physics standpoint I’m not seeing how the circumference would change unless it is about how much crown the tire has at different t pressures.

 

[roadpilot]

Interesting. I’ll have to read up on how those work. From a physics standpoint I’m not seeing how the circumference would change unless it is about how much crown the tire has at different t pressures.

If you think about it, over inflating your tires will cause them to wear in the center of the tread, while under inflating will cause them to wear on the outer edges of the tread. That's because the circumference of a tire changes based on pressure.

 

[krisk]

If you think about it, over inflating your tires will cause them to wear in the center of the tread, while under inflating will cause them to wear on the outer edges of the tread. That's because the circumference of a tire changes based on pressure.

I agree that makes sense. I wasn’t thinking about the center of the tread bulging with higher pressure, which would result in a larger circumference.

 

[Zig]

I agree that makes sense. I wasn’t thinking about the center of the tread bulging with higher pressure, which would result in a larger circumference.

• Note: Spare tires do not have TPMS.
  
  ^their note

 

[Neggytive]

Toyota vehicles with full size spares on wheels matched to the car (5 alloy wheels) do have TPMS sensors, when people complain their TPMS light is on and they have filled the tire, the first thing I do is check the spare tire pressure.

It is usually very low as nobody checks the pressure on them when they do a L.O.F., and the days of a 5 tire rotation are long gone

 

[Neggytive]

I don’t see how low pressure could decrease circumference thereby increasing wheel speed. The radius decreases, but it is not a circle and the circumference is simply stretched out further on the road and is exactly the same as when fully inflated. It seems to me unless the tire is slipping on the rim the wheel must turn at exactly the same speed regardless of tire pressure.

If you can't see, look closer.

Tires are not solid, look at how much a tire on a drag car expands when it is launched

There is also Boyle's Gas Law

I don't know how it works ( actually I do I have a Engineering degree) all I know is the cars I see come thru the shop and what I read in various trade magazines that come in the mail

 

[roadpilot]

• Note: Spare tires do not have TPMS.
  
  ^their note

Donut spares won't have them, but many of the full size spares will.

 

[Zig]

Donut spares won't have them, but many of the full size spares will.

Just found it interesting a sensorless system that “In this system, the vehicle’s ABS wheel-speed sensors calculate air pressure based on wheel-rotation characteristics.” can’t figure out the spare (their note on their page of info)

 

[krisk]

If you can't see, look closer.

Tires are not solid, look at how much a tire on a drag car expands when it is launched

There is also Boyle's Gas Law

I don't know how it works ( actually I do I have a Engineering degree) all I know is the cars I see come thru the shop and what I read in various trade magazines that come in the mail

It does make sense with the changes in crown across the tread as well as the width of the contact patch with changing tire pressure. I was originally, in error, only thinking about the tire in two dimensions instead of three.

 

[kinelisch]

When I took delivery of my 2024 S650 it came with the exact sensor broken (Front Drivers Tire) and I was annoyed from the beginning. I have an appointment to check that out. I have 1,500 miles on her hopefully they don't blame it on me for whatever reason.

Sponsored