THE EXHAUST MANIFOLDS ARE FAULTY AND CRACK ALLOWING DEADLY CARBON MONOXIDE EXHAUST GASES TO ENTER THE CAB OF THE TRUCK WHILE THE VEHICLE IS IN OPERATION. THIS COULD CAUSE THE DRIVER TO LOSE CONSCIOUSNESS AND CRASH. IT WAS ONLY AFTER MY 6TH LONG ROAD TRIP (3+ HOURS DRIVING) DID I DISCOVER I WAS BEING POISONED BY CARBON MONOXIDE. I TOOK MY TRUCK TO AN EXHAUST REPAIR COMPANY AND AS SOON AS I MENTIONED MY VEHICLE THE TECHNICIAN TOLD ME HE WAS 99% SURE I HAD A CRACKED MANIFOLD. HE LATER CONFIRMED THIS WITH A DIAGNOSTIC TEST WHICH REVEALED BOTH MANIFOLDS CRACKED AND LEAKING EXHAUST FUMES INTO THE CAB. THIS COULD HAVE KILLED ME JUST SITTING IN A PARKING LOT! I THOUGHT I WAS JUST GETTING BAD HEADACHES FROM THE LONG DRIVE AND MY NAUSEA WAS FROM THE EXTREME HEADACHES. AFTER THIS HAPPENING SO MANY TIMES I KNEW THERE HAD TO BE MORE TO THIS. THINK ABOUT SOMEBODY DRIVING, BEING POISONED TO THE POINT TO WHERE THEY PULL OFF THE ROAD TO REST AND TRY TO SLEEP OFF THEIR HEADACHE IN A RUNNING VEHICLE TO STAY WARM AND END UP DYING. NISSAN NEEDS TO FIX THIS. I DON'T WANT A NEW DEFECTIVE MANIFOLD, I WANT A FIX!