Truck prices have been insane for many years now... they have become fashion statements instead of the work tool they were originally intended to be.
Same camp as @ramn4ver, own a 1993 F350 7.3 IDI Turbo Diesel. Short of getting totaled in an accident, I likely will never by a newer truck. Cheaper to keep and completely overhaul what I already have.
When the time comes, new engine is about $5k, new trans around $2.5k. Much cheaper than $60+k for a new diesel.
The trick is to keep up with the maintenace and care. Truck is always covered when not in use and undercoated annually with Fluid Film. I've done quit a bit over the years, front end rebuilt with poly bushings, replaced all the sagging cab mounts with poly bushings, new clutch/pressure plate/flywheel... are the bigger items.
Best part, completely paid for, no monthly payment approaching the cost of my mortgage. Just 4 months of payments on a new diesel would pay for a new engine in my truck.