Had the wife's 100 at the dealer for an oil change. I still haven't fixed her o2 sensor and asked them to give me a quote. Way too expensive. Also asked about heater tees. No leaking, just preventative. From seeing all of the pics on here I figured it was a big problem and maybe they repaired them all the time and wouldn't be too expensive. Service writer said he has never heard of the issue. I know he has worked there for several years and seems like a sharp guy. Is this just because of the small number of 100s out there or is it really not a common problem. Not a big deal either way, just thought it was odd.