Thanks for your response, though I do not agree. If it were a weather issue, I would think that the same problem would occur with plastic caps, which it does not. I've been all over the web and called around to a few repair shops - the issue is the metal caps corrode and become fused to the stems. Lexus put the metal caps on, not me. I was fortunate that two of my metal caps were stolen and I replaced them with plastic caps, which is essentially saving me on those two tires. I will now have to break the valve stems and replace the tmps sensors on two of my tires. Lexus sucks - I'll never get another.
aluminum will corrode as plastic does not. oem caps are aluminum. we see this all the time and a simple fix is some di electric grease. it will not corrode. all tpms sensors have these caps. it is from the manufacturer of the senswors, not lexus.