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| | | Forums66 Topics128,036 Posts1,055,450 Members48,422 | | Most Online14,466 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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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Dec 2007 Posts: 23 Apprentice | | Apprentice Joined: Dec 2007 Posts: 23 | I have found a radiator the owner claims is for a 55-59 Chevy. The numbers on the radiator are: 3135642 r11a 56h.
Any help? | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | may be - R11A is on the 5-9 Chev rads I have, but the H numbers [Harrison] I've seen on them are all H-55, and the number I have off 1 is 3133342 .... there'll be a different design for Chev and GMC, and there may be different ones for big bolts
a good pic would help decide if it's the same as yours, or if you don't have one at all, get measurements to check against your core support
Bill | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | looks just like the right thing, and may be useable as is, I'd go for it
Bill | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Isn't the 56H the date code (1956, August)?
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | might be, but I believe the H is for Harrison, it's always there regardless of the number, and in the form "H 55" not 55H - I've never seen any other letter
Bill | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Bill, I think my 54 radiators have a date marking as you describe: H-54 (I'll double check this tonight). A Google search came up with a Corvette site that stated that the some Corvette Harrison radiators had a year/date code (nnA: 19nn; A for Jan, B for Feb, C for Mar, etc.). I do not really know what the 56H refers to (but it is clearly on BobB's radiator). Tim | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 |  I'd always thought the H number was the year of the design, the 55-59 all being the same, H 55Bill | | |
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