@Rzeppa, the photo of the frames reminds me of one I snapped years ago, this being Petersen Toyota in Ft. Collins back in May 2016.
tl;dr These are 2nd gen Tacoma frames.
The rest of story is the ones in your photo look like Tacoma, too. The 2005-2023 Tacoma frame was double wall, open 'C' from roughly the front doors back. That's kind of the tell to my eye, anyway.
Toyota has an active warranty extension campaign due to frame corrosion. For my 2008 it was known as "Limited Service Campaign E0D" and for 2011-2017 it's "Limited Service Campaign K0D".
https://static.nhtsa.gov/odi/tsbs/2014/MC-10109518-9999.pdf
https://static.nhtsa.gov/odi/tsbs/2019/MC-10169416-9999.pdf
It actually started on 1st gen trucks as far back as 1995. The root of the problem was traced back to Dana/Spicer, who was the sub-contractor who actually made Tacoma frames. They did not properly apply corrosion protection I guess is the official story.
https://www.reuters.com/article/bus...-toyota-to-settle-tacoma-claim-idUSTRE70B7KZ/
The LSC document has a flow chart the required you to take your truck in for inspection so they could look at the extent of the rust. If there were no perforations you got a CRC rust coating, if there were perforations greater than 10mm they would replace your frame. And, I'm not kidding, the test used a calibrated (12 to 16 ounce) hammer swung with "light to moderate force" for the test. So if your frame was not damaged it probably was after that. The wrench thinking he was doing you a favor by wailing on your frame.
It's not unlimited, it's based on date of first use, when the truck was first registered. It's still an active campaign it seems for at least another 4 years on 2017 models, based on ZKA program replacement appears to be 12 years after DOFU on them. I don't know if it was extended beyond that.
Back in 2018 the cost estimate was $11,000 for the replacement. Now I gotta think it's a $20k bill to Toyota for each replacement.
One upside is the frame, 51001-04480 for mine (list is $4,433.72), is still in active production. Maybe next time one of those 25% off and free shipping deals comes up maybe I ought to squirrel one away.