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We frequently see questions regarding TPMS rebuild kits so we decided to put this post together to help answer some of those questions.

First, a brief overview on the two types of TPMS systems (indirect and direct) that are found on today's TPMS equipped vehicles.


Indirect TPMS

  • An indirect TPMS system measures tire pressure from the rate of tire revolution via the wheel speed sensors that the anti-lock brake system uses.

Direct TPMS

  • A direct TPMS system utilizes a pressure monitoring sensor within each tire/ wheel assembly that transmits tire pressure to the TPMS control module. It is this system, which is also the most common, that need TPMS rebuild kits.


What is a TPMS rebuild kit?

A TPMS rebuild kit contains all of the necessary components to rebuild the valve portion of the TPMS sensor of either a metal or rubber sensor. The actual sensor portion is not serviceable and goes untouched.


What's the difference between a metal sensor and a rubber sensor?

The difference is the type of valve used. Metal sensors utilize a rubber grommet and retaining nut as well as a rubber seal on the valve core. A rubber sensor utilizes a rubber valve stem and a rubber seal on the valve core. Here's a picture to better illustrate:




What is the difference between a metal sensor and a rubber sensor rebuild kit?

The difference is the included valve components. Here's an exploded view to illustrate:




When do I need to purchase a rebuild kit?

Rebuilding the valve portion of the TPMS sensor ensures an air tight seal and reduces the chance of early sensor replacement due to normal wear or corrosion. We recommend a new rebuild kit anytime the sensor is removed from the wheel and when signs of wear or corrosion are present.


What does a TPMS rebuild kit cost?

Prices range anywhere from $3.00 to $14.00 depending on the manufacturer and type of sensor. TPMS rebuild kits are sold per sensor (4 sensors would need 4 rebuild kits).


How do I know which rebuild kit I need for my vehicle?

To determine which rebuild kit is correct for your vehicle, you'll need to look at the valve stem that's currently installed. If it's rubber, you'll need the rubber valve stem rebuild kit. If it's metal, you'll need the metal one.


We hope this information provides you with the knowledge necessary to keep your TPMS sensors functional and your vehicle running safe down the road. If you have further questions regarding TPMS rebuild kits, feel free to ask them here or contact your local Discount Tire.

For more information on TPMS and other tire and wheel related topics, please visit our Information Center.
 

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Very well done! I tend to be the guy who fields a lot of the TPMS questions, so have attempted to explain this before. I put together (not nearly as nice a job) something like this some time ago for a Subaru board. Mind if I swipe it (with credit given to the source)?
 

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Thank you, sir!

I'm a multi-repeat customer of Tirerack, but I guess I need to give you guys a serious look on my next purchase!
 

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Thank you, sir!

I'm a multi-repeat customer of Tirerack, but I guess I need to give you guys a serious look on my next purchase!
My pleasure!

I'm not sure if you're familiar with our company or not, but we've been in business for over 50 years and have 900 stores nationwide. Safety and total customer satisfaction are our top priorities so we'd love the opportunity to earn your business. We also guarantee the lowest out the door price on all the tires we sell. If a competitor has a cheaper advertised out the door price, we'll beat it :cool:
 

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It's an olde timey thread (aren't they all?!) but questions....are still a'comin' :)

Our 'new' to us '05 Sienna came with a set of studded winter tires on it mounted on the (very corroded!) stock rims. A 2nd set of wheels with nearly new M&S radials mounted came included in the deal. I actually changed the wheels in the PO's driveway as the snow hasn't started to fly (yet!). I will assume the original wheels have the TPMS sending units in them - I want to buy a 2nd set for the other wheels. Recommendations? Keep in mind my favorite store is called eBay. 4 monitors with shipping $20 USD (from PRC). Are they plug & play? Compared listings at RockAuto (another favorite) - some are programmable and some are 'daily driver'. Has anyone else done this? Is the dealer the only "safe" route? So many questions - but I've got time (only 68yo) :unsure: Thanks.

PS I notice that you can buy these sending units in two different broadcast freqs.: 315 Mhz & 433 Mhz. What freq. does the Sienna use?
 
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Short answer for ACE is "none of the above". The Sienna got Direct (sensor style) TPMS in 2007. All vans built after 2007 use a relatively ancient 315 mhz system supplied by TRW. Very few vehicles use this older protocol.

Your 2005 is indirect, and uses wheel rotational speed as measured by the ABS sensor to compute if one is turning faster than the others, indicating that it's inflation pressure is lower.
 

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Longer answer for anyone else listening in: Preprogrammed sensors are very specific. There are probably 50 different part numbers out there for cars sold worldwide. Sienna TRW sensors and a number of other 'first generation' had their metal valve integral with the sensor body. You could change the nut and gasket, but that was about it. If the shank corrodes, or you can't get the valve core out, you had to toss the entire $50 assembly out and buy new.

The new trend is blank programmable sensors. A garage only has to stock a few part numbers, and just dials up the car model specific protocol (a transmission code that matches the vehicle and a specific code that identifies itself) and programs a rewriteable portion of the sensor memory with an RF pad or handheld tool. The sensor body has a screw mount, and you can change out the valve assembly at will, metal or old-style rubber.

These tools have become ubiquitous, to the level that even oddballs like me go out and buy our own and program our own blank sensors for building winter tire packages. The tools can be used to update the onboard computer when you rotate in a new set of 4 tires each season, or you can make "clone" sensors with the exact same coded so that the vehicle doesn't even know the tires have been swapped out.
 

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Short answer for ACE is "none of the above". The Sienna got Direct (sensor style) TPMS in 2007. All vans built after 2007 use a relatively ancient 315 mhz system supplied by TRW. Very few vehicles use this older protocol.

Your 2005 is indirect, and uses wheel rotational speed as measured by the ABS sensor to compute if one is turning faster than the others, indicating that it's inflation pressure is lower.
Hmmm, well thanks for the schooling :) According to what I understand then, it wouldn't matter what wheels are installed on my '05, the TPMS is monitoring the pressure 'by guess and by golly'. Thanks.
 

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If you happen to acquire wheels on ebay that have them, you'll have something to resell. If it's a whole assembly bolt-on package ready to go (tires on wheels), just leave and ignore them.
 
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