Usually 90k is the replacement point. I can't imagine it wouldn't have gone by now if it hadn't been changed. But still it'll need to be replaced again at 180k miles regardless. That'll be about a year from now. As someone else said above you'd need the water pump too (cheap part, same labor).I just had that work done on my 01 TL and it cost about $800. No small job, but still cheaper than buying something else.You might see if you can use that as a negotiating point on the price. Check the tires, too. If it's gonna need new tires soon that's another negotiating point. Tires ain't cheap these days (I just dropped $700 on a top of the line set).