Small block to big block radiator swap

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Dallinz

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I got a hell of a deal on a champion radiator for a 1998 Chevy k3500 and from what I could tell the radiator supports seem to be the same size it’s just a larger cutout. I’ve got a 1999 Yukon OBS with the 350 inside of it and it’s my off road toy but she keeps overheating. I’d like to know if this swap from the small block radiator to big block radiator would be possible. (And apologies if this isn’t the right area for This question. This is my first post )
 

exp500

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Go to a GM parts website and ener the VIN for the K3500. Then do the same for your 350 based truck.
Overheating is kinda rare on these, The clutch fan moves alot of air. Give it a spin test hot and cold.
 

Doubeleive

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I got a hell of a deal on a champion radiator for a 1998 Chevy k3500 and from what I could tell the radiator supports seem to be the same size it’s just a larger cutout. I’ve got a 1999 Yukon OBS with the 350 inside of it and it’s my off road toy but she keeps overheating. I’d like to know if this swap from the small block radiator to big block radiator would be possible. (And apologies if this isn’t the right area for This question. This is my first post )
You should just need the larger shroud if it is like the nbs
 

Sparksalot

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I got a hell of a deal on a champion radiator for a 1998 Chevy k3500 and from what I could tell the radiator supports seem to be the same size it’s just a larger cutout. I’ve got a 1999 Yukon OBS with the 350 inside of it and it’s my off road toy but she keeps overheating. I’d like to know if this swap from the small block radiator to big block radiator would be possible. (And apologies if this isn’t the right area for This question. This is my first post )
This used to be a really common practice back in the 80s and earlier to deal with pulling travel trailers over the Sierra Nevada. Three and even 4 row cores in radiator.

If you still have a fan clutch, how old is it? They do fail over time and contribute to heating issues.
 
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Dallinz

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This used to be a really common practice back in the 80s and earlier to deal with pulling travel trailers over the Sierra Nevada. Three and even 4 row cores in radiator.

If you still have a fan clutch, how old is it? They do fail over time and contribute to heating issues.
It’s a brand new fan clutch. The radiator is just really rusted out and I’m pretty sure it’s blocked up somewhere in the radiator or inside of the engine. I’ll be doing a flush in the next couple days and I’ll update from there.
 

Sparksalot

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It’s a brand new fan clutch. The radiator is just really rusted out and I’m pretty sure it’s blocked up somewhere in the radiator or inside of the engine. I’ll be doing a flush in the next couple days and I’ll update from there.
The tubes may be scaled up. If so, it’s not repairable. Back in the dark ages, when radiators were brass, you could disassemble them and rod it out. Modern aluminum and plastic radiators are disposable.
 

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