Owners of 2005 through 2010 Nissan Frontiers, Pathfinders and Xterras are reporting premature transmission failure, according to The New York Times. The issue is caused by radiator coolant leaking into the automatic transmission, which subsequently destroys it.
The issue is caused by the radiators. In October of last year, Nissan extended warranty coverage on the radiators of 2005-2010 Frontiers, Pathfinders and Xterras from three years or 36,000 miles, to eight years or 80,000 miles. The New York Times reports that Nissan said only "a small percentage" of its Frontiers, Pathfinders and Xterras would be affected. The problem was caused by a cracked oil cooler tube, causing a coolant leak.
Fast forward to today, and many Nissan truck and SUV owners are reporting that the radiator issues have affected the vehicles transmissions, causing premature failure. Lance Wiggins, Technical Director of the Automatic Transmission Rebuilders Association told The New York Times that what's happening is the radiator cooler tanks are rupturing, forcing coolant into the five-speed automatic through the transmission cooler lines. The result of this is transmission failure.
The problem partially lies with Nissan's warranty extension. When Nissan notified owners of the radiator problems, they allegedly failed to acknowledge that the issue could allow coolant to enter the transmission and take it out of commission. Also, by moving the coverage from 36,000 miles to only 80,000 miles, it left many Frontier, Pathfinder, and Xterra owners out to dry, because many early buyers had already driven past the 80,000 mile cutoff. Without coverage for the radiator, owners would be forced to pay for the repairs out of pocket. For those who decide to risk it, the result could be transmission failure.
Nissan Spokesman Colin Price told The New York Times that Nissan would cover transmissions damaged by coolant, as long as they met the extended warranty guidelines.
Source: The New York Times