Recently my dad totaled his 2020 silverado with no damage to the engine. I’m considering swapping the engine for this 2020 pickup into my sierra. I haven’t been able to find any info online about how to do this. I was wondering if anyone knew of an adapter kit or had some tips and tricks for a swap of this caliber.

I bet nobody has done this.

Either way, you're going to want to give a few more details. From what you describe, the Silverado could have a 6.6L diesel V-8, a 3.0L diesel inline-6, a 6.6L/6.2L/5.3L gasoline V-8, a 4.3L gasoline V-6, or a 2.7L turbocharged gasoline 4-cylinder. I've never heard of anyone mating any of these to a 4-speed automatic, let alone going to the trouble of programming this combination.

Is anything wrong with the engine currently in your Sierra?

thanks for the response! So the silverado has the 5.3L v8 and 8 spd gearbox. I was planning on keeping the two together because the sierra is currently running a less than reliable 4l60E. The sierras engine currently has frequent misfires and throws random problems here and there (timing chain to name one) but nothing out of the ordinary for a 170,000 miles.

Okay. Then all you'd have to do is make all of the electronics work together and/or swap all of the electronics from one to the other. Gauges, entertainment stack, lights, etc.

I'd venture to say that the 8-speed has had more non-longevity issues in its seven years than the 4L6x has had in its 21 years. Might be the same argument with longevity issues included, but the 8-speed hasn't been out that long yet. This is the only transmission I've ever heard of where the manufacturer'* defense for the problems with this transmission it to say that a class action lawsuit for these issues should be dismissed as it described a design defect on all 8Lxx transmissions, and not a materials and workmanship issue, and therefore is not covered by warranty,

What happened to this poor engine? 170,000 miles is not an extreme amount of miles for a 5.3, unless it has been beaten and/or neglected the whole time. I've never heard of a timing chain going out on one, and the other issues seem repairable with a little diagnosis. Certainly less work than swapping a modern drivetrain in.