One of my favorite personal peeves. The spare tire carrier.
Glide out carrier is demonstrated in this dealer video at 12:57:
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The two crossmember pieces, one ahead of and one behind were there to support the tire. I @$$ume to keep it from rocking. If you didn't order a spare when you bought the truck you didn't get the crossmembers. Ask me how I know.
Speaking of which, when I tried to buy them from the dealer only one was still available. The rest of the parts were also NLA. The parts guy recommended the winch type holder which I bought, but missing the other crossmember I never got around to installing. Fast forward several years and the internet exists, I'm able to find all the parts to put an original carrier and crossmembers together and I discovered the same thing @RaiderL discovered. That fugger is heavy! So at some point I'll be installing the winch. But I'm keeping the original too. Belt and suspenders, you know. And I will never hate the factory tire carrier regardless of how heavy and awkward it is. What I hated was having the spare in the truck bed. That was frikin' awkard.