Originally Posted by Henn28

The trickiest part with the 4.4 set up is not screwing up the diff to oil pan seal on the install. If you nick that flimsy little o ring while cursing and manhandling the diff to get it into place, it will leak. The 4.4 has a metal protective ring that gets installed over the o ring, but my experience was that it kept falling off the diff. Alignment needs to be perfect in the way in.