Working on a 2014 RX350 with a noisy belt tensioner pulley. I shopped very carefully for the pulley, and all my research indicated that I needed 16604-0P011, which supersedes 16604-31020. Pulley came in, pulled the old one, and they do not match. The tensioner pulley has a 24mm bearing, and the new pulley has a 13mm bearing; apparently it's an idler pulley. Does anyone know the correct part number for the tensioner pulley? I can get a Chinese pulley with the right dimensions from Amazon for $20, but I would really rather get OEM quality. Thanks!

In the pictures, the original pulley is the black one on the left. The 16604-0P011 is the red one on the right.

 

Nevermind, I found it: 16620-31031

 

16620-31040
https://www.amayama.com/en/part/toyota/1662031040

16620-31031 might fit but I think that's for RWD cars.

 

16620-31040 is the entire tensioner assembly.

 

so is 16620-31031
https://www.lexuspartsnow.com/parts/...620-31031.html

 

Right you are. That explains why the part number only pulls up aftermarket pulleys. Looks like Toyota doesn't sell just the pulley. I'll call the dealership on Monday and see if I can get a different story from them.

 

Did you consider quality aftermarket pulleys from Gates or Continental etc https://www.rockauto.com/en/catalog/...er+pulley,6956

Although I don't know if any of these will actually fit based on your post.

 

Those are all idler pulleys, not the tensioner pulley.

 

The cheapest alternative is to press out the bearing and replace the bearing. Use quality replacement though. If this gives you half life at marginal price, at next failure you can do the assembly.

Although when it comes to tensioner, I would replace the whole assembly, but that is just me.

Salim

 

That is what I did on my 1995 Ford Explorer when an idler pulley went bad on the old V6. It was not that difficult to press the bearings in and out. There are YouTube videos with MacGyver like tips. I think I may still have a few of those bearings laying around.
I found one and it has a 17mm hole, same as the ones on Rock Auto for the idler. I bet they would work if an idler goes bad on my RX.

 

Listings for just the pulley will say, fits 16620-31031
There is no Toyota part number for the pulley itself at least not that I can find. You have 5 choices

OEM
Aftermarket
Aftermarket bare pulley
Source the bearing
Repack the bearing

 

Dealership confirmed Toyota doesn't sell the pulley separately. Febest it is.

 

Given the extent of the labor and tight spaces to get in there, I am going to do the same but with all OEM parts (inclusive of the tensioner bracket).

My question now is ... given that the car is over 10 years old but with just over 50k miles, should I change out the water pump one time?

 

LOL, you're going to replace the tensioner? Guessing you have no idea what that involves...

 

No - wait until the water pump fails unless you need another project and feel it is worth doing while in there replacing the tensioner assembly.
Water pumps when failing will give plenty of warning via noise or minor leaks. Usually by noise that sounds like marbles in a can as the internal seal failed and coolant dilutes the lubricant around the bearings. They can fail anytime or last forever.