This is the type of custom repair I really enjoy. This customer wanted a gear ratio change but the bearings had eaten away at the housing after a couple of hundred thousand miles. Most shops would have junked the housing and the customer would be forced to spend more money and time finding a donor housing at the salvage yard. I see this failure quite often, for some reason many of the Dana 60 housing castings seem to be a bit shy of material in this area. I have opened many of these up and have noticed that there wasn’t even any bearing support half way around from the factory. Over time the bearing eats into the housing up to a 1/4 inch. This one only went about an 1/8 inch.

The repair procedure is simple. Install a line boring bar and cut back the damage, then shim the carrier bearing to compensate for the machining. In really bad cases a spacer is made similar to a Chevy 12 bolt carrier shim to make up the difference. In this case the carrier bearing caps were also worn .004” so the caps were machined .005” to provide a tight fit.

Here is the cutting tool set up. Note in this picture the bearing caps are removed for clarity but upon machining they are used to lock the boring bar in centerline.

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Here is the entire set up, using an air powered portable milling head. The motor turns the boring bar at 50 rpm and advances the cutter .001” for each revolution proving a chatter free cut.

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Each side of this housing had to be resurfaced, one side about .030” and the other about 1/8” . And here is the final result, a housing better than new, as there is now more surface area to support the bearing race.

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