Heater Core----copper Or Aluminum?

BKM48198

15 Year Member
Jun 7, 2008
377
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Ypsilanti, Michigan
I will be needing to replace my heater core soon and want the best heat possible, which gives better heat ? I hope to do this job once and never have to do it again after reading about how much work is involved. AutoZone shows a Copper/Brass one for about $45 and Aluminum for about $25, what are the pro's-con's of the two? Should I just spend the extra money on a Motorcraft heater core, they seem to be close to $90? Any brands to stay away from?
 
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Yes. You should spend the $90 on the Motorcraft unit. Why? Hmmmm.... How long has the core in your car been there? :O_o: That's why. :)

Folks with aluminum radiators often like to match them with aluminum heater cores. It makes complete sense except that the OEM heater core is a known quantity while you take your risks with brand X cores.


Good luck. :)
 
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When ever mine start leaking I am going to go with a Motorcraft core. Just for the simple fact that the one in the car is nearly 25 years old and still doesn't leak.
 
Yes. You should spend the $90 on the Motorcraft unit. Why? Hmmmm.... How long has the core in your car been there? :O_o: That's why. :)

Folks with aluminum radiators often like to match them with aluminum heater cores. It makes complete sense except that the OEM heater core is a known quantity while you take your risks with brand X cores.


Good luck. :)
I do have an Aluminum radiator but don't really care about what the heater core is made from, not into making sure they match but if someone makes a really good quality aluminum HC then I would spend the extra money on it. I'm more interested in the best heat and getting a really good quality HC, I don't want a cheap part that I'll need to replace in 3 to 5 years.
 
When ever mine start leaking I am going to go with a Motorcraft core. Just for the simple fact that the one in the car is nearly 25 years old and still doesn't leak.
Mine is just over 25 years old and I think it is starting to leak, I am leaning towards the Motorcraft but want to hear what others that have replaced theirs already have used and had good luck with. I have heard that a HC from newer Mustangs might fit too, so that is a possibility if they are better.
 
You as a human, will not be able to detect a difference between an aluminum or copper core as you sit in the car.

Chasing a certain heater core because of it's thermal transfer properties won't net you a better result one way or the other.

Between the two materials, the copper is better at transferring heat. What does this mean to you and passengers? Nothing really. The car cabin will be warmed in roughly the same amount of time and to the same temperature. The materials just don't make that much of a difference in this circumstance.

Really the only thing you need to be cautious of is poor material quality and workmanship on the core that you purchase.

Do NOT forget to install the heater core restrictor back into the same position that you find it in. Running without that restricter will generally make short work of any heater core.
 
Mine is just over 25 years old and I think it is starting to leak, I am leaning towards the Motorcraft but want to hear what others that have replaced theirs already have used and had good luck with. I have heard that a HC from newer Mustangs might fit too, so that is a possibility if they are better.


You're chasing ghosts.


Edit: Sorry about that. I sometimes get into a hurry and don't explain.

Your heater core is 25 years old. In that time, it has been filtering the 'crud' from your cooling system. There's no doubt that the old one is plugged and also full of a buildup of scale. By simply replacing the one that is in there with it's sibling, you're going to notice a significant change.

All of that scale is preventing good heat transfer between the cooling system fluids and the shell of your heater core. You will indeed be getting better heat.
 
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You as a human, will not be able to detect a difference between an aluminum or copper core as you sit in the car.

Chasing a certain heater core because of it's thermal transfer properties won't net you a better result one way or the other.

Between the two materials, the copper is better at transferring heat. What does this mean to you and passengers? Nothing really. The car cabin will be warmed in roughly the same amount of time and to the same temperature. The materials just don't make that much of a difference in this circumstance.

Really the only thing you need to be cautious of is poor material quality and workmanship on the core that you purchase.

Do NOT forget to install the heater core restrictor back into the same position that you find it in. Running without that restricter will generally make short work of any heater core.
I had one of the HC hoses blow out a couple years ago and replaced it with a hose that did not have the restrictor in it and didn't notice it for about 2 months, that could have caused a problem in mine. I'm not 100% sure mine is leaking but since it is 25+ years old and I'm going to be replacing the seat upholstery and maybe the carpet I don't want to have problems after I do that. I also am replacing my fuel pump which works great but is also 25+ years old and could go out at any time, I'm trying to get ahead of the problems.
 
I had one of the HC hoses blow out a couple years ago and replaced it with a hose that did not have the restrictor in it and didn't notice it for about 2 months, that could have caused a problem in mine. I'm not 100% sure mine is leaking but since it is 25+ years old and I'm going to be replacing the seat upholstery and maybe the carpet I don't want to have problems after I do that. I also am replacing my fuel pump which works great but is also 25+ years old and could go out at any time, I'm trying to get ahead of the problems.


I added to my post above for clarity. I didn't like how I left it.

Here's the thing about heater cores in our cars. They're kind of a pain in the ass to change. So for as long as I have had a Fox Mustang (longer than the age of many of our members) this discussion comes up. There are some good heater cores out there that are NOT made by Ford. That's right.... occasionally someone screws up and gets it right by mistake. hehe The problem is that over the years, the ONLY heater core that has been consistently reliable is the OEM unit that the car came with. :)

If you don't have an in-line restricter, you need to get one. I think LRS probably has them.
 
Ithis may have no relevance whatsoever, so take it for what it Is:

I have owned two houses, both built in the early 2000s. I have put new HVAC systems in both houses, one had a quality system, the other was bottom of the line, they both failed in less than 8 years. My father n law is still rocking the same heatpump he installed in 1985.

My HVAC guy told me that there were a lot of aluminum cores being used in then80's, and then a swap to copper happened again. He told me the copper ones don't last long at all and are more prone to corrosions. He also said that manufacturers are going back to aluminum in many cases due to it lasting longer.

Now, you heard my source for this info, and it's application, I guess you can decide if it is applicable to heater cores too.

Joe
 
I added to my post above for clarity. I didn't like how I left it.

Here's the thing about heater cores in our cars. They're kind of a pain in the ass to change. So for as long as I have had a Fox Mustang (longer than the age of many of our members) this discussion comes up. There are some good heater cores out there that are NOT made by Ford. That's right.... occasionally someone screws up and gets it right by mistake. hehe The problem is that over the years, the ONLY heater core that has been consistently reliable is the OEM unit that the car came with. :)

If you don't have an in-line restricter, you need to get one. I think LRS probably has them.
I noticed the old restrictor in the blown out hose and checked the new one, when I found it didn't have one in it I installed the old one in it. I have had very good luck with most of the OE parts that came on the car but not as good of luck with replacement parts, even those with the Motorcraft brand on them. There is an old saying that " They don't make them like they used to" and I believe that, Ford changed the Heater cores from being Copper-Brass to Aluminum in most new vehicles for some reason, is it just for cost and weight savings or was it due to corrosion problems? Chemicals used in antifreeze 25 years ago are not the same as the ones used today, just because the OE one lasted this long does not mean a replacement from the same manufacturer will last the same length of time. I just want the best HC I can get so I don't have problems again, I'm not getting younger and my body doesn't twist the same way it did when I bought the car in 1989 so I don't want to have to try to be a contortionist in 5-10 years to get to some of the screws. If I do get an aluminum one I want it to be fully welded and not be crimped together like some of the cheap ones are, I bought a radiator with crimped on ends that blew apart on me and left me on the side of the road for 2 hours waiting on a tow truck.
 
Ithis may have no relevance whatsoever, so take it for what it Is:

I have owned two houses, both built in the early 2000s. I have put new HVAC systems in both houses, one had a quality system, the other was bottom of the line, they both failed in less than 8 years. My father n law is still rocking the same heatpump he installed in 1985.

My HVAC guy told me that there were a lot of aluminum cores being used in then80's, and then a swap to copper happened again. He told me the copper ones don't last long at all and are more prone to corrosions. He also said that manufacturers are going back to aluminum in many cases due to it lasting longer.

Now, you heard my source for this info, and it's application, I guess you can decide if it is applicable to heater cores too.

Joe
Most car makers have switched to aluminum for heater cores also, that is part of why I am wondering if there is a better heater core than the stock copper ones.
 
I am not sure the aftermarket has been around long enough to test the longevity theory. NOT to discount the quality of OE parts, either, but Im 99.9% certain that if the core I installed from late model resto was ever to be questioned, they'd make it right before you could formulate an argument.
 
Most car makers have switched to aluminum for heater cores also, that is part of why I am wondering if there is a better heater core than the stock copper ones.

I think the bigger question is what sort of coolant/water are you putting in the car. That would have a bigger impact on how the copper/aluminum radiator/core fares over time.

My personal preference for cooling system materials is copper. Short of silver, it is the best at thermal conductivity. With that said, an aluminum core will still get plenty hot and heat fine.

As for corrosion, you'd be surprised what can cause that. It could be a matter of using waaay too much distilled water in your cooling system (Not good for aluminum or copper), or adding those silly additives to your system, to putting ground wires where they shouldn't be and creating ground loops or proper conditions for electrolysis in your cooling system which leads to corrosion.


My thoughts. As someone who's pulled a Mustang dash off in 2 hours countless times...it's still a crappy job. I hate doing it with a passion, and would like to avoid it with a passion. I know motorcraft quality has slipped, but i'd rather install an OEM core, vs a cheap parts store core and avoid doing the job again in 2 years.

I replaced my core once in 1999 with a motorcraft copper core..and it's still going strong.
 
Heh... I replaced mine in 2005 and same.

Almost 20 years on the first with 10 and counting on the second.


As for corrosion, you'd be surprised what can cause that. It could be a matter of using waaay too much distilled water in your cooling system (Not good for aluminum or copper),


Why would distilled water be bad for a cooling system? It has the least amount of suspended particles/minerals? Are you referring to the water and antifreeze mix?
 
Why would distilled water be bad for a cooling system? It has the least amount of suspended particles/minerals? Are you referring to the water and antifreeze mix?

Well, i meant to refer to 100% distilled water. In general you want "some" minerals and ions in your coolant mix, and most modern coolants contain this corrosion inhibitors. So Distilled water plus coolant (as to control what is introduced) is the way to go. 100% Distilled water....can't recommend.

DI water is even worse (although many don't have access to this) as it lack both minerals, and IONS. I've seen DI water corrode stainless steel over time. You definitely do not want DI water in your cooling system.
 
Well, i meant to refer to 100% distilled water. In general you want "some" minerals and ions in your coolant mix, and most modern coolants contain this corrosion inhibitors. So Distilled water plus coolant (as to control what is introduced) is the way to go. 100% Distilled water....can't recommend.

DI water is even worse (although many don't have access to this) as it lack both minerals, and IONS. I've seen DI water corrode stainless steel over time. You definitely do not want DI water in your cooling system.


I thought that, that was what you meant but I wasn't sure. lol