Xoutpost.com - Idler Pulley and Tensioners

While doing my hose, pump, and thermostat job on my 4.4i, I spun the tensioner and idler pulleys and they seemed to be a little loose.

So I pulled one off and went to my local BMW dealer.

They want to sell the complete tensioner arm (for both belts) for about $90 each and the idler for $60.

I told them The arm and springs are fine and I just need the pulleys. No Can Do, they only sell them as a set.

Pulling off the other two pulleys, I could see that they are all the same unit. They all have the same part number markings. So there really is no need to buy the more expensive arms when you just need the pulleys -- just buy three of the lowest cost part.

Still looking for the pulleys, I went on-line and was able to find the pulley wheel and bearing for $25 each + shipping.

Looking further, I found that the part number used by all the auto stores is the same for pulleys from BMW, Toyota, Chrysler, and a host of other manufacturers. Based on this I decided to give the lowest priced pulley a try.

I found the pulley for a Chrysler/Jeep (2010 Compass) on-line for $10 + $9 shipping. But before Ordering I decided to check out the local store to see it up close and make sure it was indeed the same part. I took my original with me and found that yes - they are indeed inter-changeable parts (with the Chrysler being 1 cm less wide than the BMW spec version). Since the large belt rides in the middle of the pulley with 1.5 centimeters unused pulley space on either side, I decided to buy three and call it a day. The local Chrysler dealers charged me $20 each (I had to go to two different dealers to get the three pulleys).

So, price wise, it looks like I am saving $180, don't have to order on-line, and have my parts today. Performance wise, I can't say yet.

BTW, two of the three old pulleys spun freely - a little to freely. So when I removed them, I spun them on my finger and although they didn't sound too bad, I could feel occasional lateral roughness so they have to go.