CQHall

I need to replace my dual idler pulleys. Number 8 on the diagram here (specifically the rear one closest to the engine):









OEM is around $700. Should I bite the bullet and buy the OEM or are there quality aftermarket solutions available?

machild

The bearing is the most important part of any of the idler/tensioner pulleys. You can always upgrade the bearing in the non-plastic pulleys. Somewhere on here is a discussion on all pulley replacements and I detailed all the bearings I replaced (complete rebuild for less than $100). Do a deep search for it. Here is a new aftermarket double pulley setup if you are interested. Easy money at $160. https://www.rockauto.com/en/moreinfo...75924&jsn=1138 If you just want to replace the plastic pulley the Dayco 89130 is the replacement item. Pastic pulleys genrally can't have the bearings replaced. https://www.rockauto.com/en/moreinfo...01965&jsn=1144

Muhtish

I have replaced the bearing on my E55 and it didn't help, so I went with next best thing, FCPeuro.
https://www.fcpeuro.com/products/mer...ley-1132020419
Hope this helps you.

bbirdwell

Or rebuild it as described in other posts. Dayco 89130 plastic pulley plus a NSK 6203 ZZC3 bearing. Do *not* purchase the cheap Chinese-made "five bearings for $10" version. Go for a quality manufacturer; will still cost you less than $20 for a quality bearing.

https://mbworld.org/forums/w211-amg/...uild-27-a.html

machild

The post I refernce above is #59 of the link Barry has posted here.

CQHall

Thanks for the prompt replies, everyone! I'll let you know how it goes.

CQHall

I went with this option.

FYI: Even though the pulleys are right there on top, it's impossible to swap them without removing the fan shroud...which means also removing the plastic aerodynamic tray underneath. This is because it's impossible to get a wrench with a bit on it in the 2 inches of working room between the bolt and fan shroud. Unless you happen to have a set of low profile bits and torque wrench.