The added safety features of a 4th gen are worth it to me.
a 2000 4runner doesn't have stability control, and ABS is optional. 2001 and newer have them. Some people don't like those features, but the truth is they do help, and they can often do better than even a skilled driver. They can react faster than you can, and they have more information about, and control over, each individual wheel than you have.
Crash tests were not as advanced back then, so even if the 3rd gen did well, it may have been tested against a lower standard or gone through fewer tests than newer vehicles, depending on who was testing (IIHS or NHTSA).
Side airbags are optional on 4th gens before 2008.
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