I'll throw this out there to anyone with a vehicle they're considering getting rid of for any mechanical reason... This doesn't really apply to something that is rusting really bad.
This spring, I noticed a shudder in my transmission. I have a 2018 silverado with at the time 140k miles.
Little bit of research, and it's fairly common for these transmissions to go out between 60k-160k. I thought about it for awhile. Considered trading it in, considered waiting for it to blow and dropping the $5k on a rebuild, then considered one of those extended warranties...
Long story short, I have an extended warranty that'll cost me $3,700 over the course of 4 years or 100,000 miles, and with the transmission being an almost guaranteed failure point, along with the potential for lifters to go out, I figured I might as well be covered.
I did my homework and landed on Endurance for a warranty company after talking with transmission shops and auto shops in my area. Still doesn't give any warm fuzzy feelings while waiting for the transmission to go out. Especially when driving 2,500 miles round trip to chase elk 2x a fall.