The correct upper idler pulley
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Member
Joined: Nov 2017
Posts: 87
Likes: 29
2009 GL450 SOLD / 2011 GL550 SOLD / 2013 GL450 current daily
The correct upper idler pulley
Before I begin, the tools you will need for this is:
- E14 socket (6 pointed star) to remove the upper idler pulley.
- 17mm socket to use on the serpentine belt tensioner to release the tension enough to remove the serpentine belt. You will apply pressure counter-clockwise to release the tension (the same technique for installing the belt as well.). Visually you will not be able to see where you connect the socket onto the tensioner. It's hidden behind the belt. You will have to feel for it first with your fingers.
So for the last couple of days I've been hearing chirping coming from under the hood, based on the sound I was pretty sure that one of the pulleys was going bad. Well today it was confirmed. While in the garage detailing the inside on my beloved GL with the engine idling the chirping all of a sudden stopped. I got nervous and quickly turned off the car.
The upper idler pulley disintegrated. Only the bearing housing was still intact. The serpentine belt was resting behind it and was amazingly unscathed.
I went to the Benz dealer, Napa, O'Reilly's, Auto Zone and Advanced Auto with no luck.
Ebay has them but it would take too long to receive it.
Amazon has them but it would of taken longer than the Benz dealer to get one delivered.
The part number on the old one reads A2722021019 but by accident I ran across an ACDelco one on Amazon with the part number ACDelco 38099 and the part number A2722021019 stamped right across the bearing but it's states it's not compatible with the 2009 model GL450. Although It's compatible with 2011 GL450.
Ebay makes that same claim about the AC Delco one not being compatible with the 2009 GL450.
NAPA has one with the A2722021019 stamped on it but it too is not listed as being for the 2009 GL450. Their part number is NBH 38099.
The Oreilly one has the same specs but has the part number of 38099.
I ordered the one from Amazon and it will be here Monday. I will also swing by O'Reilly's in the morning and pick up the version they have to see if it fits. I'll let you guys know if it fits.
- E14 socket (6 pointed star) to remove the upper idler pulley.
- 17mm socket to use on the serpentine belt tensioner to release the tension enough to remove the serpentine belt. You will apply pressure counter-clockwise to release the tension (the same technique for installing the belt as well.). Visually you will not be able to see where you connect the socket onto the tensioner. It's hidden behind the belt. You will have to feel for it first with your fingers.
So for the last couple of days I've been hearing chirping coming from under the hood, based on the sound I was pretty sure that one of the pulleys was going bad. Well today it was confirmed. While in the garage detailing the inside on my beloved GL with the engine idling the chirping all of a sudden stopped. I got nervous and quickly turned off the car.
The upper idler pulley disintegrated. Only the bearing housing was still intact. The serpentine belt was resting behind it and was amazingly unscathed.
I went to the Benz dealer, Napa, O'Reilly's, Auto Zone and Advanced Auto with no luck.
Ebay has them but it would take too long to receive it.
Amazon has them but it would of taken longer than the Benz dealer to get one delivered.
The part number on the old one reads A2722021019 but by accident I ran across an ACDelco one on Amazon with the part number ACDelco 38099 and the part number A2722021019 stamped right across the bearing but it's states it's not compatible with the 2009 model GL450. Although It's compatible with 2011 GL450.
Ebay makes that same claim about the AC Delco one not being compatible with the 2009 GL450.
NAPA has one with the A2722021019 stamped on it but it too is not listed as being for the 2009 GL450. Their part number is NBH 38099.
The Oreilly one has the same specs but has the part number of 38099.
I ordered the one from Amazon and it will be here Monday. I will also swing by O'Reilly's in the morning and pick up the version they have to see if it fits. I'll let you guys know if it fits.
Last edited by mrathell; Jan 8, 2018 at 08:38 AM.
Thread Starter
Member
Joined: Nov 2017
Posts: 87
Likes: 29
2009 GL450 SOLD / 2011 GL550 SOLD / 2013 GL450 current daily
I just installed the one from O'Reilly's and it was a 100% match and German made. So I can confirm you can use any of the pulleys referenced above.
Here are the prices:
MB Dealership - $90
O'Reilly's - $48
Napa - $43
Amazon - $30
Here are the prices:
MB Dealership - $90
O'Reilly's - $48
Napa - $43
Amazon - $30
