The original radiator top tank cracked. Right along the raised level rectangle where the part information is molded on, close to the left end, and began dripping coolant on the floor, and spraying onto the air cleaner box. I replaced it with a Denso 221-3420 aftermarket (RockAuto, $68, 1 yr warranty), it was a perfect fit, exact replica, down to the raised pad that cracked on the original, and materials / workmanship looked to be equivalent.

I did also replace the two bottom rubber mounts with Nissan part 21508-4P000 ($11 ea. at the dealer, $7 online), they were completely hard and should they break apart, would leave the plastic lower tank banging directly against the support, and the hoses with Gates hoses from RockAuto. I did see reviews of the Dayco bottom hose, that suggested the molded bends in it are not correct, and it can rub against the steering shaft. The bends in the Gates hose kept it clear like the original.

I won't repeat what is in the FSM. I plugged the AT cooler lines during the swap, with the solid end of drill bits. The only challenge was fastening the fan shroud to the new radiator. The top parts of the two shroud tabs that are screwed to the radiator top tank had cracked and broke apart when it was removed. I bought 1" stainless steel fender washers and regular s/s washers from the local hardware store. Using one of each was a good fit for the left side tab where there was 1/2 of the tab left, enough for the washer to sit flat. On the right side, the 1" fender washer was a little large, and I filed flats onto the washer on the bottom and the right side, making it a perfect fit. There was a only quarter of this tab left, and I used the broken off pieces of the tab as spaces to make both washers sit flat and tight to the tab. The shroud is now more securely attached than before.

Since the factory foam seal between the radiator top tank and the upper radiator support bar had deteriorated away previously, I had already replaced it with an all-purpose foam weather seal. I used two layers of this 7/16" thick foam (Frost King R734, 3/4" wide), as I could not find one that was 1" thick, and stuck it to the radiator support. I needed to patch a section that had come off during the radiator replacement.

Since I had only used a year on the "OEM brand" 5 yr green Asian spec coolant, after doing a multi-fill flush with distilled water, I filtered the coolant through a paint strainer and reused. The coolant had no cloudiness or other contamination. I floor jacked the front of the SUV as high as it would go, and filled it slowly until coolant overflowed from the vent pipe at the back of the engine and from the radiator filler. I was still left with a 1/3 gal of original coolant, which after it fully cooled overnight, I added half directly to fill the radiator and the rest to the reservoir. I did not have heat on the 10 min easy-driven drive home, but did the next day, after topping up the radiator. The following morning after that, the reservoir level had dropped to the full mark.

All in all, an easy and affordable job.

Great, what's the rationale for lifting the front as high as possible?

Tilting the engine so that the front, and the top radiator hose, is higher, provides a better path for air to move out as the engine fills from the back with coolant (less chance of trapped air.) And the reason to pour the coolant in slowly, allowing air to move out as the coolant enters.

Mod: I see now I have the wrong year in the Title, damn dyslexia is getting worse with age. Can you correct to '03, and then delete this post. Thank you!

Aren't '02 and '03 the same platform? Dont delete this post, this is invaluable info for future reference.

One last tip: tighten the wire hose clamps on the large diameter hose connecting two metal pipes on the right side of the engine just below the head. A leak from there runs down the exhaust heat shield dripping on the floor behind where this hose is.