I have just under 40,000 miles on my 2002 Tundra Limited TRD 4x4.... I've had the Rack and Pinion, fan belt, battery, and all the brakes replaced under warranty. I've been reading all of the nightmares concerning the cracked manifolds and faulty O2 sensors.
During cold mornings I have the exhaust leak sound under the hood. I brought it to a dealerships attention back when it was under warranty but they couldnt hear it. There is no doubt that i have at least one cracked manifold.
As far as the O2 sensors are concerned...... I feel like im driving a ticking time bomb.
I found this car review on another site that I believe is worth sharring. In my opinion, this guy has hit the nail on the head!
Reviewer Ted Larson is correct in being concerned about his exhaust manifolds. This is a serious problem. It happened to me at the 36,300 mile point, and Toyota did not want to cover it under warranty (they later reconsidered, but it took a month of calling/negotiating and was very distressin and painful). THIS IS NOT A MINOR PROBLEM!!! The cost to replace themanifold is $1,000. It is obviously a design/manufacturing problem and it seems like Toyota is just trying to ignore the problem until warranties run out and it becomes the problem of the buyer to fix. Additionally, when they mess around with the manifolds they dirty up the oxygen sensors which soon fail and cost $250 to replace. On top of that, it's about a 50/50 chance that when they pull out the oxygen sensor they're going to strip the delicate aluminum manifold, and so it will have to be replaced again at a cost of $1000. This is very bad for Toyota's reputation, and they should stand behind their customers on this.