Radiator Compatibility for 1948 Roadmaster

[Sir Gonzo]

I have a 1948 Roadmaster (series 70) with a Dynaflow automatic transmission. Does anyone know what years use the same radiator as the '48? Are there other GM makes from the same year (or thereabouts) that are the same as the Buick? Is there a source where I could buy a new '48 radiator?

 

Thanks!

p.s. The transmission cooler on this year is separate from the main radiator.

[The 55er]

According to the Hollander Interchange the only radiator that fits your car is a 1948 Buick with Dynaflow.

[56 Buick]

I could certainly be wrong but I thought the 42 to 48 radiator for the 60, 70 and 90 series was the same.

Anyway, if you have a current 48 radiator, are you able to have a repairer break it down and repair it? 

If you don't have a current 48 radiator, are you looking for something period correct or just a replacement?

There will likely be aftermarket producers who build something vintage looking that fits or there will likely be those aluminium builds you could use.

[The 55er]

3 hours ago, 56 Buick said:

I could certainly be wrong but I thought the 42 to 48 radiator for the 60, 70 and 90 series was the same.

Anyway, if you have a current 48 radiator, are you able to have a repairer break it down and repair it? 

If you don't have a current 48 radiator, are you looking for something period correct or just a replacement?

There will likely be aftermarket producers who build something vintage looking that fits or there will likely be those aluminium builds you could use.

It's true a 42 to 48 radiator for 60,70 & 90 series is the same. It's the With Dynaflow part that makes it a one year only item according to the Interchange.

[56 Buick]

Thanks, that makes sense.

[Sir Gonzo]

@56 Buick My Buick runs hot and overheats here in Arizona when it gets over 90 degrees F. Among other potential causes for the overheating, I'm exploring two options when it comes to the radiator.

 

The first is to find another compatible radiator from another Buick and have it upgraded with a modern core and built-in tank transmission cooler so I can keep the original look, but have the modern efficiency and ease of future repair.

 

The second option is to buy a new aluminum replacement radiator and I found a place that has them for various '30s, '40s, and '50s Buicks, but of course, not for a '48. But I was thinking that they might not know that, potentially, an early '40s radiator will fit just fine in a '48, which is why I was asking about the range of years that might be compatible.

 

If you and @The 55er are thinking that '42 through '48 are the same radiator, then I might be able to go with the second option because it will bolt in and fit with no problem and the fact that I have a Dynaflow transmission won't really matter in this case. The difference between the Dynaflow and non-Dynaflow radiators is the core type (cellular vs. tube and fin) and the cap pressure (7 vs. 13 lbs.). I would bet the frame and fit are the same across all models.

 

Any thoughts? Thanks!

[56 Buick]

Sorry, I can't answer that. 'Same' on paper doesn't always relate to 'same' in practice. Is it possible to 'see and measure' actual cars? Suitable cars may possibly be found at a vintage wrecking yard maybe? Or query sizing and photos from the radiator fabricator shop doing the aluminum radiator to compare. Sorry I can't be more help.

[Dan O]

I searched for a replacement for my '49 Roadmaster (with dynaflow of course) and could not find any new ones being built or that came close.

 

I had mine rebuilt with a new core, etc.  The rebuilder "did me a favor" and made the body thicker so the fan would no longer fit.  We cut down the spacer and it works now.  Radiator work is expensive now - about $900 for mine.

[Stripgear]

If the engine has never been out of the car (rebuilt),  it might just be full of rust. My car would overheat when I got it. I removed the rear freeze plug and was able to flush out enough rust to fill up  a 1 lb. coffee can. Problem solved.