Automatic Transmission Cooler problems of the 2010 Nissan Rogue

One week after purchasing the car, I took it on the highway where the speed limit is 75 mph. After about an hour the speed slowed to 65, then 60, then 50 etc. , even tho the gas pedal is to the floor. Cruise control also had no effect. I had to pull over in a very dangerous situation. After a few minutes, I got back on the road and up to speed again. This has happened now 3 times in 2 days. . So obviously I don't feel safe taking it on a busy highway. From what I gather, this is a transmission cooling issue and is remedied by installing a $1200 external cooling unit of some sort that Nissan is aware of but won't address(?) I am not happy.

The car developed a problem where the transmission was slipping and I noticed fluid leaking. Took to dealer, and I had additional coverage for repairs and break down. They told me the enclosed transmission developed a leak due to corrosion. That corrosion damage is not covered, and it cost $400. 00 to remove the part rather than replace it. The car has a grinding vibrating sound when driving. The cvt is known to have this issue, and the transmission is sealed so you can't check your fluid level and it is required to only use Nissan manufactured transmission fluid. The cvt is tied into a fail safe mode that can be activated by high temperature in the engine. A cooling kit has been recommended but I have read mixed posts as to the dealerships charging to put it into the car. The car has been known to totally lose power while driving if it goes into this fail safe mode or when the cvt just fails completely. Warranty was extended to 10yrs/120000 miles for cvt.

Vehicle was traveling 70 on the interstate on cruise control when the speed suddenly dropped 20 - 30 mph and the engine started racing forcing us to pull the vehicle off the road. The vehicle idled properly then drove properly the remainder of the trip. This scenario has happened several more times, all but one while on cruise control. I took the vehicle to the service department at a Nissan dealership. Mechanic diagnosed the problem as the issue in Nissan service bulletin ntb14-002a:::---- 2008-2012 Nissan Rogue; reduced performance due to cvt fluid temperature protection logic the maximum vehicle speed is, or was, reduced by the cvt fail-safe logic after continuous operation under the following conditions: 1)high rpm and/or high speed driving (rpm of 4000+ or speeds of 65 mph [104. 6 km/h] for 1. 0 – 1. 5 hrs. Or more) 2)driving in ambient temperature of 96 degrees or higher 3)climbing steep or extended hills for 6 miles (9. 6 km) or more 4)whine or rattle type noise occurring during reduced engine performance (vehicle speed decrease) ---- Nissan has a known and intentional issue in the transmission system while operating under some very normal conditions. Nissanusa consumer affairs initially told me that the warranty had been extended for this vehicle and the problem would be covered. They have since indicated that the repair for this issue (adding an external cooling mechanism to the transmission) is not covered by the extended the warranty. Looking for some sanity here. Nissan needs to fix the transmission (design?) problem under their extended warranty.