Heater core replacement. Are they all the same from all vendors? Where to buy?

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Nasty-LSX

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Ok, Got the cooling issue fixed on the 85 K20. I need a new heater core. I know better then to buy from a cheap $20 item.
There is copper ones and then the aluminum ones. Whats yalls experience with product brands or does it really not matter.
This is going to take alot of work to swap out, so I want to get the best I can get to avoid re doing it. I found this company
who sell all A/C stuff with great reviews even off Amazon. What cha think? Its from ( OLD AIR PRODUCTS.COM )

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PrairieDrifter

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I got a brass/copper unit from summit like 7 years ago now. Fit perfect and has held up great.
 

Nasty-LSX

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I thought about that also. Thats why I was asking if it really matter what material it was.
 

PrairieDrifter

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I can't speak scientifically but it seems like copper/brass holds the heat better when confined like that. Supposedly aluminum is supposed to be a better heat conductor.

I think the problem with the aluminum ones are they don't fit perfect. So you have air gaps around the core when you shouldn't have any.
 

Grit dog

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Napa one fits like ****. A little too big. Think it’s aluminum but can’t remember. It worked and appeared to be quality but had to (carefully) cram it into the heater box and barely got the heater box to seal up.
If summit gets good reviews I’d go with that. One of the places that still doesn’t sell crap parts. IMO.
 

TotalyHucked

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Not all heater cores are created equal. I got the one Napa lists for these trucks and it was too small, aluminum and the outlets weren't in the right spot. Couldn't even get it to fit right in the box. Went to my local radiator shop and they were able to order me the correct copper one, it matched the original perfectly and was only ~125 IIRC. I'd highly recommend checking with your local rad shop.
 

Robert Bare

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Depends on how much you want to spend,lol! But, here is some info-
Copper/brass tends to clog and plug faster, if you run crappy coolant
Aluminum tends to rot/leak faster if you run crappy coolant
Aluminum WILL give you more heat, much better performance.
Top of the line?? Can get both, I would chose aluminum, but I live in cold climate
You can get quality brass, and quality brazed/welded aluminum
nowadays, remember, almost any part you can buy from a parts store for 60-70 bucks, you can buy off the net for 35.
Brassworks is known for their high quality, but the prices will shock you.
And remember, on these trucks, replacing them is actually an easy job.
 

Grit dog

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Not all heater cores are created equal. I got the one Napa lists for these trucks and it was too small, aluminum and the outlets weren't in the right spot. Couldn't even get it to fit right in the box. Went to my local radiator shop and they were able to order me the correct copper one, it matched the original perfectly and was only ~125 IIRC. I'd highly recommend checking with your local rad shop.
Lol and the Napa one I got was too big…WTF? I do recall “adjusting” the coolant pipes a bit but they were in the right location anyways.
 

Robert Bare

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Lol and the Napa one I got was too big…WTF? I do recall “adjusting” the coolant pipes a bit but they were in the right location anyways.
Well, because of "Bidenomics" I recently went back to work, social security ain't cutting it, as I like to eat and have power, So, no wrench swinging at my age, am part time at a NAPA store.
Anyway, what I have seen last 5 months, the top "aftermarket stores in our area all have troubles. Local Carquest and Oreilly cannot keep help.
BUT, anyway, our store is independent, 98% of our sales are to shops, and the owner has been phasing out the cheaper line of "NAPA required to stock" items. If they are shipped in, they get sent back. We got bit too many times especially by their cheapo brake parts. But, in some instances, there is no big supplier of quality parts, heater cores is one of them. I think we have 3 "brands", and all are mainland China made,lol. Same way with radiators. Even working there, at times I still get parts from Rockauto, because I can get the brand I want,lol.
For those wondering, yes, NAPA is shifting away from WIX as a filter supplier. Why? Most wix are American made, and NAPA did not like their price increases. Yes, I disagree with that line of thinking,also. Anyway, they are being phased out, and replaced by filters from MANN+HUMMEL GmbH. So this will undoubtedly mean more imported filters, as they don't have the capability for manufacturing in the US. So, I expect to see more China,Taiwan, Vietnam, etc made filters.
Oh well.
ALSO! Be aware, there are many items on the NAPA website that I cannot even order, in our area. And not just us, but all NAPA stores, varies by region. So, many good products are out there that stores are restricted from. Makes no sense to me.
 

Grit dog

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Well, because of "Bidenomics" I recently went back to work, social security ain't cutting it, as I like to eat and have power, So, no wrench swinging at my age, am part time at a NAPA store.
Anyway, what I have seen last 5 months, the top "aftermarket stores in our area all have troubles. Local Carquest and Oreilly cannot keep help.
BUT, anyway, our store is independent, 98% of our sales are to shops, and the owner has been phasing out the cheaper line of "NAPA required to stock" items. If they are shipped in, they get sent back. We got bit too many times especially by their cheapo brake parts. But, in some instances, there is no big supplier of quality parts, heater cores is one of them. I think we have 3 "brands", and all are mainland China made,lol. Same way with radiators. Even working there, at times I still get parts from Rockauto, because I can get the brand I want,lol.
For those wondering, yes, NAPA is shifting away from WIX as a filter supplier. Why? Most wix are American made, and NAPA did not like their price increases. Yes, I disagree with that line of thinking,also. Anyway, they are being phased out, and replaced by filters from MANN+HUMMEL GmbH. So this will undoubtedly mean more imported filters, as they don't have the capability for manufacturing in the US. So, I expect to see more China,Taiwan, Vietnam, etc made filters.
Oh well.
ALSO! Be aware, there are many items on the NAPA website that I cannot even order, in our area. And not just us, but all NAPA stores, varies by region. So, many good products are out there that stores are restricted from. Makes no sense to me.
I’d say that’s crazy but have seen Napa changing. Service is still much better and the real parts guys will tell you whether it’s junk or not. Like you just provided an example of.
Eh well, times a changin….lol.
Good to see some Napas are culling out the obvious low quality crap.
 

Grit dog

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I complain, but 30 years ago I couldn’t order a custom for exhaust system (or anything else for that matter) laying on the couch, delivered to my door by Thursday…. Lol. And the fact that I can get most any part for any old vehicle at the touch of a screen, is pretty amazing.
 

WFO

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Copper dissipates heat almost twice as fast as aluminum.
That's why it's used for soldering irons.
 

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