Alternator Decoupler Pulley

[Vibraphone]

RE: 2006 Vibe, 187K mi. Retrofit decoupler pulley. My car doesn’t have one. Maybe I’m searching wrong keywords??? I can’t believe this topic hasn’t been covered? Apologies if it already has -- pls point me in the right direction.

I’m replacing OE 18yr old alternator soon, as I get odd voltage drops using heat/fan… normal aging, I think. Question: can I add the later style Decoupler pulley, as in post-2008 Vibes?

Gates #37015P Decoupler Pulley… or even Toyota OEM #274150T060 pulley, seems like easy bolt-on for the DENSO-reman I’m buying. Seems like lots of advantages. Any downsides?

I’ll also be replacing idler pulley + belt. Tensioner seems okay.

[jolt]

If it did not come from the factory with it, it is not needed. The 2006 does not have enough electrical load that it requires a decoupling pulley. The pulley will never decouple with the small load on the alternator and the 1.8L engine. It would be a waste of time and money. Also, the ECM is not programmed for the decoupler so other issues will happen if the the alternator decoupled. If you want a decoupler then leave the bad belt on it. When the belt slips, you will have the same results as a decoupler would provide.

It is a good idea to replace the belt tensioner when ever you replace the belt. I changed my on my 2.4L. The tensioner pivot bolt was very hard to get off. I had to remove engine mount and jack up that side of the engine to get the pivot bolt out so it would clear the sub-frame in the engine bay. The 1.8L is different, so you may not run into that issue.

[Vibraphone]

Thank you. I suspected a decoupler pulley might be like the 5th toe on a dog. Just wondering, as later Matrix had 'em.