2005 Nissan Titan exhaust system problems

Dvr rear axle seal leak (which saturated brake pads leading to possible severe problem, but was caught before any situation) at 28,xxx miles, rear axle seal leak pass. Side (warranty optioned to replace whole rear end axle assembly at 36,200 miles, rear axle seal leak both sides including 3rd member seal at 60,xxx miles, rear end ring and pinion "grenaded" at 61,xxx miles (extended warranty still unsure on coverage due to lack of rear end maintenance records, I. E.

My 2005 nissan titan has two cracked exhaust manifolds. They are cracked into two pieces and are allowing carbon monixide to escape from the exhaust system adjacent to the cab of the truck. This is a potentially lethal failure due to co poisioning. Nissan has been contacted and will not assist with repairs, even though there have been hundreds of similar reported cases. My vehicle is out of the warranty period and I understand nissan's reluctance, financially, to repair the failure.