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| | | Forums66 Topics128,101 Posts1,056,179 Members48,436 | | 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: Jun 2014 Posts: 106 Shop Shark | | Shop Shark Joined: Jun 2014 Posts: 106 | I have pulled the seat and fuel tank out of Clyde. I have looked and found mo numbers on this tank other than a stenciled number 4 on the drivers front corner. To my knowledge, it is out of a 40s or early 50s Chevy truck. Anyone able to identify this fuel tank? Pictures here | | | | | Joined: Jan 2013 Posts: 2,234 Moderator: Interiors, Texas Bolters, Name that Part | | Moderator: Interiors, Texas Bolters, Name that Part Joined: Jan 2013 Posts: 2,234 | does not look like my 51 tank. My guess is it is pre 47, but i am not the professional here. | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | the under seat tank was done with the Deco series, AD tank behind the seat or on the frame, see the Master Parts Manual here, says 37-46 1/2T all the same, although there may be other tanks in that same year range that would fit Bill | | | | | Joined: Jun 2014 Posts: 106 Shop Shark | | Shop Shark Joined: Jun 2014 Posts: 106 | Bill,
Thank you for the information.
I am confused by the Manual.
It shows a 36-37 low cab (GC is my model) without filler neck holding 18 gallons.
It also shows 37-46 1/2 (single unit) with a filler neck.
That information seems contradictory. Did the 37 1/2 ton come with a filler neck or not?
What is a single unit?
Any ideas? | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | no contradiction, the manual was for ordering replacement parts, so you could get a tank with or without the neck and they'd be different part numbers, likely will be a neck listed separately as well ... don't know about the 'single unit' .... see the other parts manual, where the GC model isn't listed, might be they decided the low cab could use the same tank as the rest  Bill | | | | | Joined: Jun 2014 Posts: 106 Shop Shark | | Shop Shark Joined: Jun 2014 Posts: 106 | Bill,
It is my understanding that the 37 only had a fill hole inside the truck. Where did the external with a filler neck exit the vehicle? | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | I'm not the low cab expert, no idea what GM did then, but I'd assume there were some 37 models that had external fill necks, and ones without external necks used the same tank but would need to have the fill neck/cap added when the tank was replaced, either from the old tank or a new neck ordered separately .... what you see in the Master Parts manuals is the applications the parts applied to and what was available in the day, search in it and see if the neck is listed .... so to your original question, the tank itself from 37-46 will fit under the seat, and your tank is no newer than 46 - someone must have cut the hole in the cab to accept that filler?
Bill | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | "single unit" (SGL. UNIT in Master Parts Books) refers to panel-body trucks.
| | | | | Joined: Jun 2014 Posts: 106 Shop Shark | | Shop Shark Joined: Jun 2014 Posts: 106 | .... so to your original question, the tank itself from 37-46 will fit under the seat, and your tank is no newer than 46 - someone must have cut the hole in the cab to accept that filler?
Bill Bill, Thanks for the help. You are correct, the hole was cut by my grandfather - not a paint and body guy so you can imagine what it looks like behind the mudflap gasket.  It seems the tank I have then is for a '38 - '46 with neck. The '37 never had a neck installed to my knowledge. To fill up you lift the passenger seat, remove the cap and fill the tank. Now the decision of keeping the external neck or not. | | | | | Joined: Jun 2014 Posts: 106 Shop Shark | | Shop Shark Joined: Jun 2014 Posts: 106 | "single unit" (SGL. UNIT in Master Parts Books) refers to panel-body trucks. Thanks Tim! | | | | | Joined: Dec 2001 Posts: 14,522 Moderator: Welcome Centre, Southern Bolters, Legion Hall | | Moderator: Welcome Centre, Southern Bolters, Legion Hall Joined: Dec 2001 Posts: 14,522 | The '37 never had a neck installed to my knowledge. To fill up you lift the passenger seat, remove the cap and fill the tank.
That is correct. Been doing it for years. Most folks have never seen this and I'm always getting questions about why I split the bottom seat. Folks look at me funny at gas stations with the passenger seat raised and the pump hose going into my truck. | | | | | Joined: Jul 2002 Posts: 166 'Bolter | | 'Bolter Joined: Jul 2002 Posts: 166 | When I bought my 37, It came with an external filler neck that exited through the cab behind the passenger door. The hole that was cut looked like it could have been done at the factory but the interior trim panel & seat riser were poorly hacked to allow for the filler neck. I'm guessing mine was modified some time during it's life prior to my owning it. Mine has a 38-46 type tank. I'm still debating whether or not to keep what I have, return to under seat filling or under bed tank. So far I've been leaning toward leaving it as I bought it. | | |
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