A warning about the Superior Aluminum Radiator

[Kelpiesgmc]

I have a whole thread about the details so I won't repeat it all here, but I did want to make a quick warning about the Superior Aluminum Radiator that some of the GMC shops sell. I'm sure it's worked out fine for plenty of folks, but mine cost me months of headaches, and hundreds of dollars spent debugging and replacing other perfectly good components.

To briefly state what happened, It caused my engine to run very hot. In fact even the gentlest of hills would cause the engine heat to run away, and I'd have to pull over and shut off the engine. The coolant would boil out of the overflow reservoir.

I replaced every part of the coolant system (at least once) and did countless things to troubleshoot the problem. All said and done I must have drained and refilled the coolant system 10 times or more. Finally I replaced the radiator with a standard copper radiator and immediately the problem was resolved. I've put hundreds of miles on it since and the temps never climb above the thermostat temperature (180º). So actually now it's running a little colder than I'd prefer . I can't bear to drain the coolant again to put in a 195º thermostat. At least not yet...

I would love to do an autopsy of the radiator to learn exactly what was going on inside of it. All I know is that it's shaped distorted quite a bit in just ~40 miles of use, and it developed a leak in the bottom corner. That leak forced me to replace it, which is the only reason I even figured out that it was the cause of my troubles.

So I thought it would be good to put out a little PSA to warn folks.

I thought I'd also mention something I learned in this whole fiasco— I thought that because you don't typically see aluminum radiators that they were "Fancy" or "Superior", but actually aluminum is an inferior metal for a radiator, for one thing because it doesn't like expanding and shrinking. In addition, the copper radiator was a lot cheaper. Like 40% the cost. It was easy to source locally at a radiator shop.

So yeah, don't be fooled by that "Superior" radiator and its impressive price tag— Just get yourself a much cheaper, longer-lasting, more repairable Cooper one.

 

[LQQKatJon]

That is strange. The “superior” radiator was a fairly new thing in 2019. The one motorhome enhancement had…. Had some tank issues. So I did not want one of those.

The price of the “superior” radiator in 2019 was same or less then a copper one. I paid $699 I think back then for my superior radiator. Shipping was quick and cheap then too. They were all over ebay… but I called and ordered direct and paid the ebay price. That was less then quotes I had at the time for a copper rebuild.

I have been running that with no issues now since 2019. And must have 25,000 miles on it by now?

But looking now. Ebay shows the same one $1080+ $165 shipping?? And their website says $1180.

 

[kspriggs]

I made the mistake of junking my old radiator when I swapped to the Superior Aluminum radiator last Spring - sure wish I had kept the old.....
I have long had cooling issues that go away with the use of a severe duty clutch (I have tried 3 or 4 alternative clutch options along the way) - the Aluminum Radiator didn't change this fact: I started out by trying other clutch options and ultimately had to come back to the severe duty to keep a steady temp (I'm also back to a 180 tstat after briefly switching to a 190 when I installed the aluminum rad). So, I can't really comment too much about the Aluminum Radiator engine cooling abilities - though I suspect it did not improve anything in the best case.
I can pretty assuredly state that my use of the Aluminum Radiator last season saw:

1. Noticeable increase in transmission oil temps. I was very surprised - even after switching back to the severe duty clutch - that my trans temps were clearly running hotter than I'd ever seen them - and this was in cool spring weather. I ultimately added an external trans cooler (in line before the rad cooler) which immediately solved this problem.
2. Likely (though not measured) increase in Engine Oil temps. I deduced this by watching my oil pressure gauge with concern as it was running way below expected (below 20psi on my gauge) once up to temp and speed. I ultimately "solved" this by switching to 20W-50 instead of my typical 10W-40 - but I only have a few hundred miles to show for this and am still monitoring.

So - at least in my opinion based on these two factors - it seems the oil cooler section of the aluminum radiator is inferior to what I had in the old unit.....and I can confirm that for me it was a considerable wasted expense doing this conversion - though it does look prettier.

Kevin

 

[Keith V]

... but actually aluminum is an inferior metal for a radiator, for one thing because it doesn't like expanding and shrinking.

Actually no. Aluminum is better.
Thats why it's used everywhere. Copper is tougher yes, because it's thicker, but aluminum radiators are more efficient. You can draw an aluminum tube thinner than copper and still have good strength.
Aluminum has lower thermal mass than copper, so it transfers heat better to the air.

Yes you had a bad one, doesn't make them all bad

 

[pvfjr]

Actually no. Aluminum is better.

Copper has significantly higher thermal conductivity, which can offset a lot of the additional thickness. To say whether that's more than adequate, or not enough, we'd have to talk about the actual numbers and have a quantitative discussion rather than a qualitative one. Even then, it'd be on a case-by-case basis, so there might not be a generally correct answer here.

Thermal mass isn't a factor for steady-state heat transfer, and doesn't affect how well it transfers heat to the air.

 

[Keith V]

Thermal conductivity and thermal mass make for interesting math

 

[LarryW]

The other thing to consider is repairability. I went through three aluminum radiators before I finally went and found a copper core and had it built with an over size core. At about three years in use, all three aluminum radiators started leaking between the core and the tanks. When I took them to the local radiator shop, the guy told me that the connection between the core and the end tanks had cracked. One of the radiators, he thought it looked like the bonding between the tanks and core was epoxy. Epoxy or aluminum, so no way to repair. At three years, the warrantee was up. I've had my copper radiator now for 7-8 yrs with no issues. And if it did leak, it can be solder repaired. No issues with overheating in Arizona, California, 90+ temps two springs ago going to the Buellton GMCMI rally. Personally, from experience the most reliable way to go is rebuild the original in copper and then do preventative maintainence, changing antifreeze every 3-4 yrs. JMHO.

 

[Carl Stouffer]

I've been running a Griffin aluminum radiator that I got from Applied for over 16 years and close to 100,000 miles. Never had problem #1 with it. I guess everyone's experience varies.

 

[LQQKatJon]

I made the mistake of junking my old radiator when I swapped to the Superior Aluminum radiator last Spring - sure wish I had kept the old.....
I have long had cooling issues that go away with the use of a severe duty clutch (I have tried 3 or 4 alternative clutch options along the way) - the Aluminum Radiator didn't change this fact: I started out by trying other clutch options and ultimately had to come back to the severe duty to keep a steady temp (I'm also back to a 180 tstat after briefly switching to a 190 when I installed the aluminum rad). So, I can't really comment too much about the Aluminum Radiator engine cooling abilities - though I suspect it did not improve anything in the best case.
I can pretty assuredly state that my use of the Aluminum Radiator last season saw:

1. Noticeable increase in transmission oil temps. I was very surprised - even after switching back to the severe duty clutch - that my trans temps were clearly running hotter than I'd ever seen them - and this was in cool spring weather. I ultimately added an external trans cooler (in line before the rad cooler) which immediately solved this problem.
2. Likely (though not measured) increase in Engine Oil temps. I deduced this by watching my oil pressure gauge with concern as it was running way below expected (below 20psi on my gauge) once up to temp and speed. I ultimately "solved" this by switching to 20W-50 instead of my typical 10W-40 - but I only have a few hundred miles to show for this and am still monitoring.

So - at least in my opinion based on these two factors - it seems the oil cooler section of the aluminum radiator is inferior to what I had in the old unit.....and I can confirm that for me it was a considerable wasted expense doing this conversion - though it does look prettier.

Kevin

I will agree…. The tranny cooler and oil cooler in the superior radiator are kinda stupid??? Look down the radiator opening and all you see is what looks like a couple of coils of brake line. I cant imagine much heat transfer happens. I do run just the superior radiator’s oil cooler. But I now have a big transmission cooler.

I have always had good temps with my setup. 195 thermostat. Plastic fan and a “heavy duty” fan clutch. I had played with lower thermostat before and just found it did what others said. Controls the low temp, But not really the high temp. I iust seen larger temp swimgs with the 180. It would be at 180. But loaded up on a hill jump to 200-210 pretty quickly. And down and up the temps would jump. With the 195, the engine sticks at 195-205.

 

[LQQKatJon]

The other thing to consider is repairability. I went through three aluminum radiators before I finally went and found a copper core and had it built with an over size core. At about three years in use, all three aluminum radiators started leaking between the core and the tanks. When I took them to the local radiator shop, the guy told me that the connection between the core and the end tanks had cracked. One of the radiators, he thought it looked like the bonding between the tanks and core was epoxy. Epoxy or aluminum, so no way to repair. At three years, the warrantee was up. I've had my copper radiator now for 7-8 yrs with no issues. And if it did leak, it can be solder repaired. No issues with overheating in Arizona, California, 90+ temps two springs ago going to the Buellton GMCMI rally. Personally, from experience the most reliable way to go is rebuild the original in copper and then do preventative maintainence, changing antifreeze every 3-4 yrs. JMHO.

Just my non-radiator experience. Prople like to buy aluminum trailers now to avoid rust. But the aluminum does corrode and can give some issues. And welds can crack.

I like my aluminum trailers for the lower weight is all.

Also there are so many quality of aluminum out there. Some hold up better then others.

 

[tmsnyder]

Just my non-radiator experience. Prople like to buy aluminum trailers now to avoid rust. But the aluminum does corrode and can give some issues. And welds can crack.

I like my aluminum trailers for the lower weight is all.

Also there are so many quality of aluminum out there. Some hold up better then others.

A student club at my work had to abandon a 24 foot aluminum trailer on the other side of the country, cracks in the aluminum frame.

 

[RDunagan]

I made the mistake of junking my old radiator when I swapped to the Superior Aluminum radiator last Spring - sure wish I had kept the old.....
I have long had cooling issues that go away with the use of a severe duty clutch (I have tried 3 or 4 alternative clutch options along the way) - the Aluminum Radiator didn't change this fact: I started out by trying other clutch options and ultimately had to come back to the severe duty to keep a steady temp (I'm also back to a 180 tstat after briefly switching to a 190 when I installed the aluminum rad). So, I can't really comment too much about the Aluminum Radiator engine cooling abilities - though I suspect it did not improve anything in the best case.
I can pretty assuredly state that my use of the Aluminum Radiator last season saw:

1. Noticeable increase in transmission oil temps. I was very surprised - even after switching back to the severe duty clutch - that my trans temps were clearly running hotter than I'd ever seen them - and this was in cool spring weather. I ultimately added an external trans cooler (in line before the rad cooler) which immediately solved this problem.
2. Likely (though not measured) increase in Engine Oil temps. I deduced this by watching my oil pressure gauge with concern as it was running way below expected (below 20psi on my gauge) once up to temp and speed. I ultimately "solved" this by switching to 20W-50 instead of my typical 10W-40 - but I only have a few hundred miles to show for this and am still monitoring.

So - at least in my opinion based on these two factors - it seems the oil cooler section of the aluminum radiator is inferior to what I had in the old unit.....and I can confirm that for me it was a considerable wasted expense doing this conversion - though it does look prettier.

Kevin

I've been happy with my aluminum (Superior) radiator after 4 yrs., >50k miles. It is assisted by a heavy duty fan clutch, comes on strong when you need it and when the temp falls it goes silent. I've repurposed the original air conditioner condenser as a transmission cooler which resides in front of the radiator in its original location. I've added an additional condenser with electric fan assist with my Vintage Air air conditioner. Seems to cool pretty well. Ready to flush it and refill it.