2005 Nissan 350Z Touring Coupe 113K Automatic

Today the upper tank of the radiator split from one side to the other. Owned the car since February. Never overheated but fans have always been loud. Only drove it about 5 miles before radiator upper tank blew. Seems like a lot of pressure on upper tank. Should have popped cap as well as flowing back to the overflow tank. Obviously, I'll have to replace radiator and problably the thermostat too. May need to check fans. Saw on the forum that Nissan had some problems with the radiator fans. Any recommendations? Want to find answers and not just replace parts. Thanks in advance.

Welcome- there's probably no link between the radiator fans and the radiator blowing. In fact, the loud fan noise is probably a sign that the high-speed fans (for max cooling) are fully operational. If you want answers, start by doing a scan for codes from the ECM or BCM systems. That might lead to clues if anything is wrong as you replace the radiator.

Also, for more background on your setup: does your Z have any engine or body modifications (turbo, intake, front bumper/spoiler, etc.) that can help others understand their similar situation in the future?

You said you've owned it since February - were you able to get any history from the previous owner that might help understand why this happened? Was it tracked often, etc.? Thanks.

No modifications, all stock. I don't have specific history from previous owner. She was a middle-aged woman so I don't believe it was ever tracked. No signs of abuse.

Just a note- taking a Z to the track is not a sign of abuse. More like the Z's natural environment!

Back OT- as suggested, have you used the Z's diagnostic system to pull any codes? A good code reader is almost as essential as a 10 mm wrench on these cars.

Harbison
Had the exact same problem in the Spring. The OEM's are plastic, they're old and they fail. I got this one off of ebay. I'm almost positive that the one mishimoto sells is the same unit with their logo sprayed on. Spend the hundred bucks and swap this in. It's aluminum and larger so it'll last the life of the car with better performance.

Radiator

+ 1 for plastic being the culprit.

It's not a matter of *if* the plastic portion of the OEM radiator will fail, it's a matter of *when* (Age, climate, driving habits, and mileage will doubtless affect the when). A solid aluminum rad is a good option when it finally happens.
-Icer

This aluminum radiator will be a must-do swap as part of a water pump replacement on mine (2005 with 125k miles), or otherwise when the radiator fails (if it goes first). Thanks for posting!

I'm currently at 120k+ and as expected certain items are beginning to fail with age. I was thinking of upgrading my radiator next season and looking on the Z1 site to check pricing/parts/etc... So I'm going back and forth with them and the shop that I plan to do the install. I'd planned on getting either the Mishimoto or the Koyo since I figured either of these would be an upgrade from the OEM radiator. But one of the techs at the shop just told me that they'd have to charge more if I purchase the Mishimoto due to fitment issues and that my best bet is just buying another OEM one. But based on this thread, clearly it seems as though the full aluminum is better. Other than a direct drop in replacement, is there any reason why I should choose the Nissan radiator over an aftermarket? I was under the impression that the aftermarket one would be an improvement over the stock ones? Just figured I'd ask before ordering anything.

My radiator blew a while back (a 2005 with 190,000+ at the time) and I replaced it with OEM type radiator, although Im sorry I did. I think its better to install an all aluminum radiator because the chance of that blowing if far less since the radiator is made of all one material. I have a Mishimoto aluminum radiator in my 2005 Maxima and its better great. It fit well too. I would go with the aluminum radiator.