I would use the 3rd one with wider blades as I think it would pull more air but, I have no scientific data to back it up. I have not had the type of fan change water pump life. If the fan is out of balance, and it is on a long extension, then that could have an impact on water pump bearing wear. I am not sure which would be original.


Mike
1955 Chevy 6400 ex-flatbed (no bed now!) sold September 2023
In the Stovebolt Gallery
1958 Chevy 6400 flatbed W/dump
In the Stovebolt Gallery
1959 Chevy Suburban Owned for almost 20 years, Daily Driver -- sold May 2016
In the Stovebolt Gallery

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