Please help. Radiator replacement at 33k miles?

[LukeM35Tirondola]

Please help. My 07' M35 (33k miles) temp gauge pinned itself on "H" while driving on the highway. Dealer is telling me my radiator is not cycling fluid and needs to be replaced? Seems like a big repair for such low miles on my new infiniti. Any suggestions? Thank you. Thermostat and hoses looked fine.

[kmiles]

The car is old enough that if coolant fluid hasn't been flushed and replaced it could easily be possible. I did a radiator replacement on my former 2007 M35x last year and it as actually a fairly easy job. Took a couple of hours as I am slow, but worked perfectly. I bought the radiator on Amazon and coolant from the Nissan dealer. I would also replace the radiator cap and the upper and lower cooling hoses if they've never been replaced. I was really amazed at how much junk had accumulated in front of the radiator and the A/C condensor. Not only did the cooling system work better, cleaning out all of the junk that accumulated helped the A/C to work even better and colder.

Here is the radiator that I bought:

https://www.amazon.com/gp/product/B000I ... UTF8&psc=1

It is $88.60 on Amazon.

[LukeM35Tirondola]

Thank you that's very helpful.

[EniGmA1987]

being over 1`0 years oldf with such low miles makes me think the car has had periods where it sits a lot and is barely driven. Fluid can dry up and clog something, so like kmiles said if it hasnt been flushed once or twice in its life then it could be possible something is clogging the radiator.
My radiator had a cracked fitting and needed replacing a few years ago, I had a mechanic shop near me do the work and it only cost around $250 from what I remember. Not really a major deal.

[LukeM35Tirondola]

thanks EniGmA1987

[Larz]

Your car, and all of it's pieces, parts, wires, seals, plugs, hoses, etc is approaching 12 years old. Having such low miles makes it a rare find, but not trouble free. Mileage is an indication of usage, not an indicator of health. Just remember that 'things' wear out or brake from age as well as use. Consider that the plugs, water pump, hoses, valves, transmission, differential, seals, etc have been sitting without doing what they were designed to do ... work and circulate fluids. Even the tires are not safe much beyond 5 years whether you drive on them or not.
My advice is to gradually change out all fluids (especially brakes, coolant, gear box, power steering, and differential). Even if you don't drive it, do not let it sit with no use.
I also recommend that for repairs, you should buy your own parts (OEM or not) and find a reasonably priced mechanic who is capable of working on your car. I keep my car 100% Infiniti parts (aside from brakes and rotors because I use higher quality) and only my dealer works on my car but I am anal that way. That's why my 2009 with 107k miles burns zero oil and looks and drives like the new Q70s in the showroom.
You just need to make sure you use parts genuinely compatible with your car regardless of brand. Keeping the mileage low is only half the goal. You must also keep the entire car and it's parts young too. A 12 yr old radiator is living on borrowed time like the rest of the car. Repairs will be less frequent without high mileage, but they will still happen.

[LukeM35Tirondola]

Thanks Larz I will look into changing my fluids asap. You make a good point i'll keep that in mind moving forward.

[szh]

I always do a bunch of overkill on my cars when it comes to fluids.

Brake fluid and coolant every 2 years or 30k miles.

Transmission fluid every 30k miles - not time dependent. This fluid exchange does not change all the fluid, a powered flush gets about 50 to 60% changed (a simple drain and fill does not get more than 40% changed).

Differential gear replaced oil every 30k miles. Sometimes I let this go longer to 45k miles. It does not encounter engine heat.

Fan fluid (specific to the 2003/04 M45) every 30k miles, with the power steering flush.

Etc.

Always good to replace fluids that do "wear" out (in some sense). Changing also allows you to see if some unusual behavior is occurring in the car internals.

Yeah, it can get expensive to do them all together, so stagger them out a few thousand miles and it will not matter that much from a cost perspective. OTOH, I did have this work done at the dealer, so it was easier to schedule it all together (hefty cost, I suppose).

Z

[EniGmA1987]

Differential gear replaced oil every 30k miles. Sometimes I let this go longer to 45k miles. It does not encounter engine heat.

Even though it doesnt get direct engine heat, you should try crawling under the car after driving for a while and feel how "warm" the differential is. Basic highway driving with nothing special can put them about at the same temp as the engine, and they have no radiator to help cool them off. There is a reason they sell diff covers with extra cooling fins and capacity
Maybe even keep an IR thermometer with you so you can take it under there and check that way too, rather than burning your hand.

[EdBwoy]

Mileage is an indication of usage, not an indicator of health.

Amen!