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Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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| | | | Joined: Apr 2009 Posts: 121 Shop Shark | | Shop Shark Joined: Apr 2009 Posts: 121 | | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | They may be replacement blades (are there any codes/numbers on the blades)? I bought a generic 6-blade fan blade in the middle 70s (NAPA). One 6-blade unit is listed up through 1957. | | | | | Joined: Apr 2009 Posts: 121 Shop Shark | | Shop Shark Joined: Apr 2009 Posts: 121 | i didnt see any numbers on them ill look again . one blade came off a 216 engine in a 36 flatbed | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | What is the diameter of the center hole in both fans?
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Apr 2009 Posts: 121 Shop Shark | | Shop Shark Joined: Apr 2009 Posts: 121 | they are 1" they fit my 54 water pump perfect | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | Than it looks like you have two of the "3707662 18inch low speed 1937-55 1st truck" fans.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Apr 2009 Posts: 121 Shop Shark | | Shop Shark Joined: Apr 2009 Posts: 121 | they are both 18" blades . what does low speed mean ? are they better than the 4 blade fans ? | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | I believe they were intended for trucks that would be going slow in the fields, like grain trucks.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Dec 2010 Posts: 97 'Bolter | | 'Bolter Joined: Dec 2010 Posts: 97 | Six blade fans were also used on some of the 216s used to power Canadian army trucks. I'm not 100% sure of their reasoning but added cooling for desert warfare would make sense to me. | | | | | Joined: Feb 2011 Posts: 583 'Bolter | | 'Bolter Joined: Feb 2011 Posts: 583 | I have a 39 with a 216 engine. On a hot day it would overheat with the 4 bladed fan. I was given a 6 bladed fan. Now it will idle all day long without overheating. A big difference.
1939 Chevrolet Stake Truck
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 |
That's what it says for the 1937-1955 6-blade fan listed in the 1929-57 Master Parts & Accessories Catalog (at the link above): low speed operation, 6-blade, 18" diameter (3707662 became available in 1954 and replaced the earlier 6-blade fan 604225).
| | | | | Joined: Feb 2011 Posts: 583 'Bolter | | 'Bolter Joined: Feb 2011 Posts: 583 | I just saw an ad on ebay for a used 6 bladed fan 37-46 for $100.
1939 Chevrolet Stake Truck
| | | | | Joined: Sep 2010 Posts: 1,714 back yard wrench turner | | back yard wrench turner Joined: Sep 2010 Posts: 1,714 | I used the 6 blade off of the 216 I removed. It moves air like a hurricane. fan
Wayne1938 1-Ton Farm TruckStovebolt Gallery Forums1989 Silverado 1996 Mustang GT convertible When I die, I hope she doesn't sell everything for what I told her I paid for it! | | | | | Joined: Jul 2017 Posts: 1 New Guy | | New Guy Joined: Jul 2017 Posts: 1 | I know this post is 5-1/2 years old, but I'm looking for one of these 18" 6-bladed fans for my 37 Chev firetruck.
Bryan
Beaverton, OR | | | | | Joined: Aug 2017 Posts: 127 'Bolter | | 'Bolter Joined: Aug 2017 Posts: 127 | I am looking for one as well, for my 1951 Chevy grain truck. She gets hot really easy moving around the farm and in the field.
Thanks
1951 Chevrolet 6400
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Might want to make a shroud with a hole in it for the fan, so air is pulled through all the radiator, not just the part in front of the fan. Use a flat piece of Al, secured on the edges to the radiator frame. Fan should be partly through shroud. Get some flexible rubber mat pieces to make flaps so at speed the air can go right through the flaps-look at VW Rabbit, etc.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Apr 2017 Posts: 87 'Bolter | | 'Bolter Joined: Apr 2017 Posts: 87 | I will check a friends garage (his dad was old school engine builder/gear head). There was 3 or 4 - 6 blade fans in the corner. Also has 3 235’s, 10 265’s, 7 power glides, two complete drive trains for 54 or 55 210’s and a ton of other stuff we are sorting through.
The fans just might be the 6 blades from I 6 or from 265/283 v8s
Are there a difference? | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Check OD of blades, mounting bolt pattern and ID of shaft hole.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Apr 2017 Posts: 87 'Bolter | | 'Bolter Joined: Apr 2017 Posts: 87 | Found the fans; they were 4 blades. Will dig deeper the next time there as we aware we saw some 6 blade fans.
Ed, Thanks for info on identification | | | | | Joined: Jul 2000 Posts: 2,198 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,198 | Interesting. Why not aftermarket? Flex-a-lite
Gord 🇨🇦
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1954 1/2 ton 235 4 speed
| | | | | Joined: Dec 2008 Posts: 901 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 901 | I have one of those Flex-a-lite nylon fans on my 55 210. They sure move a lot of air.
Brian
1955.2 3100 Truck
The older I get the more dangerous I am!!!!! | | |
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