All Qashqais were sold with a 12-year anti-perforation warranty, so any external corrosion other than that caused by accident damage should have been repaired under warranty, if it has appeared at all. However, Nissans don’t have the best reputation for rust, and the Qashqai, sadly, seems to be afflicted by underbody corrosion, with several reports of 2007 and 2008 models requiring welding to the front subframe at MOT time.
The problem is engine-specific, too. The 1.6- and 2.0-litre diesels have bigger underbody splashguards, which seem to protect the vulnerable areas far better. The problem is usually apparent around the bulkhead, where the rear part of the front subframe is mounted to the bodyshell. It seems that there’s a moisture trap here that’s worse on petrol and 1.5 dci models, causing the subframe to rot from the top downwards. When inspecting one, shine a torch into the engine bay behind the block and inspect for advanced corrosion on the top part of the subframe.
If you can be sure to find a solid subframe, the best option is to clear off any surface corrosion and drown the area with rustproofing wax.
Otherwise, reports of body problems are few and far between, though some owners have reported leaking tailgates. The problem here is that the seals are easily damaged during loading and unloading. A new seal – a 20-minute DIY fix – normally resolves the problem.