Replacing Tires with TPMS can be costly.

Vehicle owners who have a newer model car or motorcycle equipped with The TPMS (Tire Pressure Monitoring system should beware of the added cost that you may incur by taking your vehicle to a local tire shop for tire replacement. If you have such a vehicle still under factory warranty and your tires are worn as indicated by the tire's tread becoming flush with your tire's wear indicators than I recommend that you have this job performed by a dealership whom is certified by the manufacturer to work on this vehicle . You may even purchase the tire else where and get them to do the installation for you. You may think that this is a more expensive route but what can happen if you don't will cost you double as witnessed first hand by a friend. This friend after shopping around for a good deal on tires that were hard to come by, found that Petboys offered them at a sale price of 4 for the price of 3. Of course not knowing the careful attention to detail required in replacing tires equipped with the TPMS he figured they should be able to handle it. The outcome was a vehicle returned to him with new tires unable to stay inflated for longer than a trip. Initially it was only two tires loosing pressure but after making his complaint and returning for his vehicle once again Pepboys handed him 4 TPMS sensors and blamed it on corroded valve stems which in this case is part of the sensor and recommended he replace all 4 valve/sensors. Corrosion can possably cause a valve stem to leak but on this newer vehicle with only 30,000 it is most likely that the valve stem was bent or crossthreaded (stripped) on installation. It is also possable to contact the sensor on the valve stem with the ram bar of the Tire bead breaker upon removal of tire.
What ever the cause Pepboys insisted it was due to corrosion and could not do anything for him except sell him 4 new sensors at $95. a piece. His dealership recommended they install standard valve stems so that he can drive the car to them for a look. Pepboys replaced all 4 sensors with standard valves. At the dealer ship he was told that the valves would not be covered since the work was performed elsewhere. His charge for the valve/sensors, installation and calibration was $700. about the same as the cost of the tires. So do yourself a favor and save the headache and extra cost involved should your mechanic have a problem with the sensors on your wheels. By taking your vehicle in to the dealership they should be covered under the vehicles warranty. If you are not sure if you have the TPMS sensors see the pictures below for a view of what they may look like installed or removed from a tire. Some types of sensors may differ with manufacturer but in researching I found this type is more commonly used on many vehicles .


To give you an idea of how the system works, the pressure sensor is attached to the tire valve and is installed from the inside of the wheel with the valve protruding through a hole in the wheel as normal. This assembly is kept from leaking by a grommet which seals the unit against the wheel when a nut is installed over the stem and tightened on the outer side of the wheel. The sensor contains a small long life battery, generally lasting 5 to 10 years. This battery keeps the sensor operating and sending a signal to a receiver mounted in the car that is wired to your instrument panels TPMS tire indicator. When your vehicle is parked the sensor is hibranating to extend the life of the battery, above a predetermined speed the transponder in the sensor sends a signal about once a minute to the reciever an if the pressure of a tire drops below 26 PSI your low tire indicator will illuminate. This light does not yet tell you which tire is low so they must all be checked and adjusted. For more information on different types or TPMS systems I found the following site to be helpful http://www.aa1car.com/library/tire_monitors.htm . Also the TPMS tire pressure monitor system light may illuminate due to changes in outside temperatures. As colder seasons approach you may find that the cooler temperatures may cause a decrease in tire pressure and the warning light to go on. This is normal and tire pressure should be checked and corrected seasonally.