The VQ40DE engine they put in the 2005-2019 models is a great engine. The RE5R05A transmission is solid as well. If you get one make sure it's either past 2008 I think or the radiator has been replaced. The stock radiators had a flaw where it would make strawberry milk by mixing your coolant and transmission fluid usually around 100k miles.
The Gen 3 tundras have the coolant to trans fluid heat exchanger on the right side of the tranny where the thermostat for the tranny fluid is located. Keep that in Mind.