My 98 Maxima has 255,000 km on it and still the original radiator and water pump , knock on wood.

I change the radiator fluid every two years, but rather than the Prestone stuff I will get either Toyota Red or maybe Nissan OEM. I believe you need 4 liters or maybe more.

My question is how long do the radiators and water pumps last.

I expect to keep the car at least two more years and maybe I should buy a rad, as using it goes on you without warning.

 

I use Preston and works great for me. The radiator fits about 6 liters. Just installed a new radiator in my Maxima (replacing the original one) at 250,000 MILES. Hope that helps. Also I hear the Nissan coolant you are talking about is good stuff.

 

It's a 9 quart system.

They don't just last a set mileage, they can go without warning. It all depends on cooling system maintenance, coolant used, and in some cases luck.