I'm at 125k on our 2010 RX350 and got a new serpentine belt to replace the original. That got me going down a rabbit hole about pulleys and tensioners. I usually replace all that I can around this time, but a tensioner is $250 and the alternator pulley is $100 by itself. So question is:

Has anybody had any issues with their pulleys? Are they worth changing proactively? Seems like a lot of money and effort to go through when I haven't seen many issues on the forum. I don't have any pre-existing issues other than a very occasional cold start rhythmic chirp.

 

If you are not currently having pulley or tensioner issues, I would not spend the money to renew them. Your new serpentine belt should be just fine.

 

There are kits available with all the required pulleys and tensioners. Depending on your mileage and tolerance for banging up your knuckles a kit may or may not be worth the hassle. Some even do the water pump at the same time since all are right there.

 

We had our idler pulley changed around 40k under warranty (2010 Rx350). Now with 125k+, it's starting again. Changing the belt is one thing, but the pulleys are PITA due to the tight space, but still doable. AS Clutchless said, knucklebusters.

 

Thanks all. I knew about the kits that had everything included, but the tensioner is not only expensive, but also requires removing the AC Compressor to remove all the bolts. So I really didn't want to do that unnecessarily, especially since I read on here a Lexus tech said he's never had to replace the entire unit before.

The alternator decoupler pulley also requires a special $90 tool kit, which would be one time use in my eyes. I guess my determination from the responses (and lack thereof) is that I'll probably just check all the pulleys and maybe replace the idler.