One advantage: when moving flow-through sensors to new wheels, you can inflate the new tires to the correct pressure without removing the sensor. With standard cap sensors, you'd need to remove the sensor, inflate, then reattach.
Moving Internal Sensors (Shop Job)
If your TPMS sensors are inside the tire — mounted to the valve stem assembly from the inside — you cannot transfer them without dismounting the tire.
What You'll Need
- A tire shop (unless you own tire mounting/dismounting equipment)
- New valve stem grommets/O-rings (they should be replaced every time the tire is dismounted)
- The sensor's torque specs (for the valve stem nut — usually 35-45 in-lbs for aluminum stems)
Step-by-Step
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Dismount the tire from the old wheel. The tire shop breaks the bead and removes the tire, exposing the internal sensor attached to the valve stem.
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Remove the sensor. Unbolt the valve stem nut from the outside of the wheel. The sensor and valve stem assembly come out from the inside.
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Inspect the sensor. Check for corrosion, cracked housing, and battery condition. Internal sensors have batteries that last 5-7 years. If yours are near end of life, replace the sensors rather than transferring old ones.
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Install on the new wheel. Insert the sensor and valve stem assembly through the valve hole from inside the new wheel. Attach the nut from outside and torque to spec.
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Replace the O-ring/grommet. Always use a new seal. The old one was compressed to fit the old wheel and won't seal properly on a new one.
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Mount and balance the tire. The tire goes back on the new wheel, gets inflated and balanced. The sensor weight should be accounted for in the balance.
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Re-learn the sensors (if needed). Some systems — particularly factory truck TPMS — require a relearn procedure so the ECU knows which sensor is at which wheel position. This may require a TPMS relearn tool or a specific procedure (driving at a certain speed, using the key fob, etc.).
Cost at a tire shop: typically $15-30 per tire for dismount, sensor transfer, remount, and balance.
When to Just Buy New Sensors
Sometimes transferring old sensors doesn't make sense:
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Sensors are 5+ years old. The battery is a sealed unit — you can't replace it. If the sensor dies in a year, you've wasted the transfer effort.
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You're changing TPMS brands/systems. Different systems use different sensor protocols. Your old sensors won't talk to your new monitor.
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Internal sensors with corroded stems. Corrosion on the valve stem or sensor body means the seal won't be reliable on the new wheel.
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The transfer cost approaches new sensor cost. If a shop wants $30/tire to transfer internal sensors and new external sensors cost $15 each, the math favors new sensors.
How TrailerWatchdog Handles Wheel and Tire Changes
One of the practical advantages of the TrailerWatchdog system is that it uses external cap-style TPMS sensors — so moving them to new wheels is a 5-minute, no-tools job. Unscrew from the old wheel, screw onto the new one, done.
But here's what makes TWD different from a basic TPMS: it doesn't just monitor tire pressure and temperature. It also monitors axle temperature — and the axle sensors stay on the axle regardless of what wheels or tires you're running. So when you swap wheels for the season or upgrade your tires, your axle monitoring doesn't skip a beat.
No relearn procedure. No tire shop visit. No wondering if your sensors re-paired correctly. Swap wheels, transfer the cap sensors, and you're towing with full monitoring — tires and axles — within minutes.
For more on how tire pressure affects your trailer, check out our complete trailer tire PSI guide.
Related Reading
Frequently Asked Questions
Can I move TPMS sensors myself?
If you have external cap sensors or flow-through sensors, yes — it's a simple unscrew/screw-on job. If you have internal sensors, you'll need a tire shop to dismount and remount the tires.
Do I need to reprogram TPMS sensors after moving them to new wheels?
For most aftermarket trailer TPMS systems with external sensors, no. The sensor ID stays the same and the monitor recognizes it automatically. For factory truck TPMS with internal sensors, you may need to run a relearn procedure so the system knows the new wheel position for each sensor.
Will my TPMS sensors work on any valve stem?
External cap sensors work on any standard Schrader valve stem. Brass or metal stems are recommended over rubber stems because the sensor's weight can stress a rubber stem at highway speed. Internal sensors are valve-stem specific — they come with their own stem assembly.
How long do TPMS sensor batteries last?
Most TPMS sensor batteries last 5-7 years. The batteries are sealed and cannot be replaced — when they die, you replace the sensor. If your sensors are approaching that age, consider buying new ones rather than transferring old ones to new wheels.
Can I use my truck's TPMS to monitor my trailer tires?
No. Factory truck TPMS only monitors the truck's own wheels. It has no way to communicate with trailer tire sensors. You need a separate aftermarket system for trailer TPMS. Learn more in our guide to RAM trailer TPMS.