I'll make this as short as possible. I own a 2008 Altima 2.5S that I've taken great care of over the last 7 and a half years. 2 years ago at about 106,000 mi the tranny went out. Towed it to the dealership and they replaced it with a factory refurbished one for free (120,000 warranty). A little over a year later while driving through the desert, it starts losing power and steaming. I figured I overheated and my thermostat is stuck since the temp gauge showed normal and half the oil burned out. Did a coolant flush and oil change when I got back. Ran fine for 3 months until it happened again. Took it to a shop where they told me that the code is for a tranny problem. Take it to a dealership. The warranty on the refurbished tranny is 1 year/10,000 mi. I am past both. They tell me I need to pay for diagnostics and to submit a claim with Nissan North America. $300 later, they tell me the tranny is fine. Suggests a tranny flush. $300 more. I go with it. My claim gets denied. So far I am $600 down. 2 days later it starts steaming again. I take it back to the dealership. They said the tranny is overheating, but structurally fine. Give me 2 options: new tranny or aux cooler for which there is a 5 month wait and $1100 price tag. I asked if they could install one that I bring. The guy said yes. I bought this: Transmission Coolers for 2008 Nissan Altima - Derale D13502 and took it to the dealership. The tech said that this is not a good idea because it might leak and suggested the Nissan one. I am a little suspicious of this. He suggested finding a cooler that is closest to the Nissan kind. I searched but could not get an answer anywhere. Can anyone suggest a good auxiliary tranny cooler? Or at least tell me that the one I have is good or bad?