I Have done just on 80k now in 4 years with half of this towing. I changed the auto trans fluid at 40k and it showed discolouration but was not burnt. I did another change a couple of weeks ago and the colour was pretty good. After the first change I couldn't get over how much smoother the box operated. I am contemplating putting an extra cooler on before leaving in May to go to FNQ again. I use Penrite lubricants and they are equal to or exceed the specs required by Nissan. My advice is not to leave the auto service too long if you are towing a van. Hope this is of interest to those who tow with their Y62. Cheers .