5 Speed auto Gearbox ATF replacement intervals

Hey Guys i have a 2006 Nissan Navara D/C 4.0 V6 Auto 4x4, now with 146 000km on the clock and i just wanted to know if any one knows when the ATF replacement intervals for the 5 speed auto gearbox are, i called a few Nissan dealerships and some of them say every 90 000km and some say every 60 000km's and one dealer even told me that the gearbox never needs to be serviced ever, so right now i'm really confused about the intervals, but i'm worried that the gearbox may have never had a ATF change all the manual says is change the Nissan specified ATF at the ATF change intervals. if some one knows when this should be done please let me know so i can start saving for the rather expensive special R4000 Nissan replacement ATF, the gearbox is working flawlessly at the moment, really smooth as silk.... i just want to make sure i keep it working this way

As far as I am aware the oil's in it for life. It's a pig to fill too, you need a special tool to pump the oil in, because there's no filler.

With that said, mine is being replaced next week. Mechanic (non-Nissan) is fitting a very large tranny cooler (no, not an air con unit for men that have visited Thailand) that will sit outside the radiator. He's going to have to add extra oil. In the meantime, I'm going to see if I can grab a temp gauge for it.

Wow that's interesting, i completely wrote off the dealer who told me that as being completely ignorant, but may be it was the other dealers that didn't know what they were talking about. so in other words i should not worry about the oil in the box unless it starts misbehaving, just one other question, i see you are fitting a cooler on yours, is there any specific reason for this and do you think i would have to do the same at some stage, i'm looking at occasionally towing a boat that weighs just under 1.5 tons on the trailer and probably another 600kg of gear and passengers, ambient temperatures will range between -10 to 40 degrees C, should i be worried about over heating the Auto Box in these circumstances?

Not really. The van in my sig currently (I will replace this pic when I get an epic one of the new van) weighed 1.8T and the pic was taken on the Ernest Giles Rd in central Australia. On the day we crossed the border into NT and discovered the 130km/h sign, it was sitting somewhere over 40C (we'd left Marla that morning) and I had the thing sitting up over 125km/h without a problem. In fact I discovered that at 120km/h or more, the TCC won't unlock even at high throttle, the car just hammers up rises instead of slowing down.

We're getting a larger cooler because the new van is 700kg heavier (2550kg total) and we're heading back into the outback this Christmas. While my driving style pretty much guarantees I won't have too much trouble regardless, I want the tranny cooler out of the radiator. Not long after I get this done, I'll replace the radiator with a racing spec one (30-40% better cooling, they claim).

Ok thanks, i'm not going to loose any sleep over the gearbox then, i highly doubt i will get the opportunity to tow anything that heavy any time soon, and mostly the boat towing will be done on highways on good roads at decent speed 120km/h or more so i'm sure if your has been ok mine will not have any problems. thanks for the peace of mind Old.Tony