I installed a Spectra Premium heater core about four years ago. The original core was a Harrison brass/copper unit which had died some undetermined time before I bought the car; it was bypassed. The new core is an aluminum unit, which it seems that most are these days. I did not replace the coolant when the new core was installed. Perhaps that had something to do with it. It's the green coolant that all us old guys are used to seeing. Now the question I have for all of you out there who have done this job, is how long do heater cores typically last in our Thirdgens? Does the type of coolant used have any effect on the longevity of the heater/radiator? My radiator, by the way, is an aluminum replacement with the plastic tank caps. It is still working just fine. So please reply and tell me how often you've had to do this.

 

Far as I know, my GTA is still on the factory core. I haven't replaced it in the 10+ years I've owned the car.

 

My Original One Lasted 28 Years.

 

I'm still running the original, factory installed heater core and radiator.

Up until 2011, I used to run regular, green Prestone with silicates. Since 2011, I've switched to silicate-free Peak Long Life (not Peak Global Lone Life).

I don't think the type of coolant has much to do with longevity; just my stupid opinion. Unless you never change the coolant or run just straight water.

 

coolant and distilled water.

as easy as it is to swap the heater core out of an 85 TA...

you should have gotten more than a few years out of it but flush the system on the next swap.

 

Original cores in all my cars and will always run green coolant.

 

Hard water probably has more (neg) effect on aluminum than the type of anti-freeze.I use green w/ distilled & sacrificial anode.Heater core is a store brand, but its over 20yr old & brass.

 

Thanks for all the replies. Those of you that still have your original brass cores can count your lucky stars; those aren't available anymore. I will definitely do a flush before I replace the coolant. I typically run distilled water in my vehicles. I have a '95 BMW that still has its original heater core.

The bad core was removed yesterday. There was no smoking gun, just a leaky core. The fact that I could drive over 20 miles home told me that it was a pinhole leak.

 

Just finished the core replacement. When people say that this job is much easier with a helper, they mean it! I worked alone and constantly had to go from the passenger foot-well to under the hood. There was a bit of tweaking that had to be done to the inlet/outlet pipes to get it to fit. That is most likely always the case. I even had the old core nearby to use as a comparison. I am very wary of doing any bending on those tubes for fear of cracking a solder joint. I drained what was left of the coolant and put in some cleaner/flush and tap water. I'll run that through the system per the bottle recommendations before draining it. Then another drain and refill with water to rinse the system before finally draining one last time before putting in some fresh coolant.

After the replacement core was in, I left the heater box open to check for leaks. Don't ask how I know this. It is disappointing to have everything buttoned up, only to see a puddle forming on the carpet.