leaving plugs in when you have AL heads is asking for probs... all the manufactors say they can go 100k miles, you need to change them about every 60k. if you break one off or pull the thread, you have to pull the head. other wise you will get metal shavings in the motor... seen wrench turns( not mechanics, there is a big diffrenc) retap heads when they are still on...
not acording to car and driver... for both 08 and 09 the number 1 and 2 least realiable cars/trucks is the cameray and the tundra... but hey its your money...
I know a few guys that have bought the tundra as a work truck, none of them have kept it more then a year. 2 of the 4 limon lawed them back to toyota.