After reading through many of the TPMS (Tire Pressure Monitoring System) related threads here and elsewhere recently, I thought I would post a consolidated list of general TPMS info. I just went through a TPMS change on my own Tundra and had to figure all this stuff out. Sorry for the long post, I hope it is helpful.
- The TPMS sensors in the styled steel wheels are not compatible with Toyota alloy wheels. There may be some compatibility with aftermarket rims. If you switch rims you will need to either get a set for the new rims (if they don'talready have them) or put in standard valves/stems and live without the benefit of the TPMS. Alloy rims use 20 degree sensors, steel wheels use 40 degree sensors. I have read about ways to retrofit rims to accommodate different sensors, but I personally think the best way to do it is get a sensor that fits your rim correctly without modification or strapping hardware onto the rim.
- I have seen sets of sensors for less than $200 on eBay. I personally bought a full set of used alloy rims with sensors and good tires for $225 last week on craigslist, I just had to be patient for the deal to come along.
- You can run your Tundra without TPMS sensors. The result is that you have to look at the warning light on the dash perpetually. I ran without the sensors for about a year, and experienced no other side effects. I have read speculation that mileage changes, but I did not experience that myself. I spoke to several techs and service advisors, and none of them had any concerns about running without the sensors except that I would not have the benefit of a low tire pressure warning.
- I strongly recommend NOT defeating the TPMS dash indicator by using tape in the instrument cluster or putting the out-of-service sensors in a pressure vessel or other methods. This is a safety-related system. If the system is not in use, it makes sense to have a reminder (dash indicator) in case someone else drives the truck, or if you sell it. Us older guys remember when we had to actually look at our tires and check the pressure manually, and if you defeat TPMS function, you should be doing exactly that. You should probably be doing that anyway, since keeping proper tire inflation can prevent improper tire wear, among other things. In my case, I am old and forgetful, and would risk forgetting such a modification. Just ask my ex-wife.
- If you change your sensors from what was on the truck when new to any other set of sensors, or even an individual sensor, you need to have the TPMS computer reprogrammed to “see” the new sensor(s). You do NOT need to write down or otherwise manually record the sensor serial numbers to do this. They can be read electronically from outside the rim/tire by anyone with the right equipment. Which brings me to my next point:
- Dealerships quoted me $100 to reprogram the TPMS system with new sensors in the wheels, and they wanted the vehicle for at least an hour. After a few phone calls, I found that Discount Tire had the necessary computer equipment to complete the reprogramming. The location I visited did it for free, and they did it in less than three minutes in the parking lot. Based on my experience I must assume that many tire dealers have the ability to perform this task, and will not charge the huge rates the dealerships want. I am guessing the Toyota dealerships simply don't want to deal with it, or have to be cautious with the liability involved with servicing a safety system.