Originally Posted by Chris Geiger
Later V6 3rd members have a hole on top of the diff for the anti-lock brake sensor. When installing this diff in an older truck you don't have a sensor to put in the hole. Some have suggested making a block off plate. Another solution is to use a 3/4", deep cup expansion plug (freeze plug). Napa stocks them, part number 219-3038. Cheap and easy to get. Easy to install: just slide a socket into the cap and tap a few times with a hammer.

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