Update - Last week, I finished the install.
Good news: The truck drives like a dream and the TrueTrac is great. Both rear wheels are grabbing dirt, rock and/or pavement and it is sweet! That stated, I replaced the whole differential first, based on bad advice. I only needed the gears changed, but I was tricked into buying the whole rearend. In any case,
I was fortunate, in that I got a complete rear-end of the same year, and same type with 3.91 gearing.The long story it that based on an internet sale, I got it and had it delivered for $1800.00. What I saw on-line and what I got from LKQ were two completely different things. I saw a complete rear end with what looked like refurbished exterior etc... I got a rusted nasty looking POS (picture included) dumped off in my driveway. I spent the time and completely removed the rust, re-used pieces from the original to complete the replacement. I got a good working rear-end with 102K miles. Drove it, but actually wanted the TrueTrac, after reading and researching.
Sooo... I went and got the TrueTrac on sale, and had it installed, after I removed the pumpkin and did the scut work (clean-up). Moral of the story - be SURE of what you need before you buy. be careful of internet sales... Lesson learned.