I appraise trade ins at a Ram store. I see 10 - 15 Rams in a week. 2010 - 2019 are the most common I see. Quite a few off brands as well, Chev, GMC and Fords
I also approve the repairs after the appraisal, so I have an end to end view on what it costs for repairs.
In general, at 100,000 miles, a Ram may need a new front axle, $500, maybe a front diff for $800. Manifolds for the Hemi - $1200, all Rams with pedal parking brake need a EBrake kit for about $1000. If they were actually operated, they wouldn't seize up and need replacement.
Then it is cosmetics - all owner caused. If the front corners of the hood corrode, it is covered under warranty for 5 years, and an attentive owner will get that repaired under warranty.
I have yet to see a bad 8-speed.
Any GM truck at 100,000 miles is an electrical nightmare, and it usually needs to go to dealer for their specialized scanners.
Just appraised a 2015 Ford XLT with the 2.7L Ecoboost and 90,000 miles. My system appraised it at $4000 less than a similar Ram. That tells me the market is worried about the turbo motors. Any higher mileage Ford Ecoboost throw up warning flags, and we go to auction with these, just not worth the head aches in repairing them.