+1: asnhe said. The tone ring is built into the bearing. It's not that uncommon for the tone ring to fail where bewring replacement is the required fix. That said, it's more likely a problem in the abs unit but that's the rub with abs fixes it can be very difficult to determine which it is.

I fortunately have two nearly identical x5s and have swapped about six items over the years to trouble shoot. Example wifes car currently is using a few items that used to be in my car: MAF, intake cam sensor and fuel pump. The maf was for trouble isolation but the other two were for quick replacement: I have her my part for instant repair and my car sat a few days until the new device came.

We've also on more than one occasion swpaped tires for an instant fix for a flat or worn out tires.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)