One problem related to frame rust has been reported for the 2004 Nissan Quest. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Nissan Quest based on all problems reported for the 2004 Quest.
There was noise coming out from the front passenger side of the vehicle and upon applying brakes the steering wheel was getting pulled forcefully to the right. Thinking that there could be some problem with the struts, I took it to the repair shop. The repair shop noticed that the passenger side of the sub-frame (frame or engine cradle) under the engine compartment was completely rusted and almost completely giving away. A high-speed bump or a sudden braking may have caused it to give away completely and could have caused the vehicle to go completely out of control. The car is old but that old for the frame to give away. This is a costly repair but more than that it is a safety critical issue that may lead to a bad accident. The only reason this may be noticed before something dreadful happened is only by chance. The drivers might be noticing other issues that prompts them to take it to the shop while the other sides of the frame are holding up the vehicle for some time. Some further research showed that this same issue has been reported by quite a few consumers (frame rusted/breaking on the passenger side), but no action has been taken thus far. I have noticed that there are numerous complaints and I-team news reports about similar issues, but no action has been taken. Remember that there are others who quietly get their cars repaired but not lodge a complaint. Given my previous experience with Nissan on a different issue with the same vehicle (cam sensor failure causing the vehicle to turn off completely (while driving) that completely jams the steering wheel and brake failure. The vehicle could only be brought to stop by applying parking brake). I don't trust Nissan to take any action unless they are forced to.