I am hoping this is the proper place for a question like this one...
A metal floor pan was included in the purchase of the 1940 KC 1/2 ton pickup I recently acquired.
The floor pan worked (sort of), in that the shift lever and hand brake both came up through holes that they fit through - but the pan was too long (front to back) to fit into the stamped floor of the truck.
When I look in the Master Parts Catalog, Group 16.545 Floor Board-Pan-Platform-Panel, the only listing that covers 1940 is for the COE. (I don't see any listings for that part for a 1939 either, except for COE.) How do I figure out what floor pan I should have? What other years might fit? Where might I look to find a used one?
The floor pan that came with the purchase is about 1" too long from front to back. I am attaching a photo of the part I received (that doesn't fit my '40 KC). Any idea of what model it might fit?
You are correct that possibly it is not the correct part.
From my experience there are a couple of other possibilities to consider. The most likely is that you have encountered the disappointing but realistic world of “reproduction” parts. It is especially difficult to make accurate replacement sheet metal parts without original tooling. Even if the manufacturer has the original tooling, it might be worn or damaged such that it will not produce exact parts.
Another possibility is that the part was made longer on purpose. This means there is extra material to trim away for a better fit.
Here is a photo of the floor pan, toe “boards”, etc. taken during the check for fit stage of my ‘46 Chevy 1/2 ton DP model.
Your pan also resembles the one on my ‘37 Chevy 1/2 ton, GC model as well. But, it is a reproduction made from fiberglass. It came that way via a previous owner.
My experience with aftermarket patch panels is they are made oversize to allow the buyer to cut at their discretion. I have also read (no personal experience) that many aftermarket panels are made using retired tooling so tolerances may be poor.
VCCA Member 43216 Save a life, adopt a senior shelter pet. 1938 HB Business Coupe 1953 210 Sedan
37Blue, The pan in your photo looks to be the same (or close) to the one I have except that the one I have has a noticeable bump manufactured into it (I assume for clearance over the transmission) and the location of the strengthening ribs. (It doesn't look as rough in real life as it does in the attached photo.)
Does the fiberglass pan seem strong enough to serve as an acceptable replacement? My goal with this truck is to create a basic driver.
It would be best to find someone who needs an original pan for a truck this fits in rather than for me to consider trying to modify this one to work in my truck.
Is there a best place on the forum to post photos of unidentified items to get a determination of what they are?
37Blue, The pan in your photo looks to be the same (or close) to the one I have except that the one I have has a noticeable bump manufactured into it (I assume for clearance over the transmission) and the location of the strengthening ribs. (It doesn't look as rough in real life as it does in the attached photo.)
Does the fiberglass pan seem strong enough to serve as an acceptable replacement? My goal with this truck is to create a basic driver.
It would be best to find someone who needs an original pan for a truck this fits in rather than for me to consider trying to modify this one to work in my truck.
Is there a best place on the forum to post photos of unidentified items to get a determination of what they are?
Thanks!
Nick The pan in my photo is a reproduction piece too. I had the original pan, but it was too far gone with rust and hole to be usable. That one also had the domed hump. My guess is your floor pan might be for a ‘41-‘46 model? I can’t see the measurements in your first photo very well. But, they look to be about 19 3/4” by 34 3/4”? That would be very close to those matching the ‘41-‘46 models; and measure 19 3/4” by 34 7/8”.
The fiber glass pan on my ‘37 has held up fine, at least for my needs. It’s at least 20 years old. I don’t know the vendor source. It measures 16 3/4” by 34 7/8”.
Jim Carter Truck Parts may still sell these sheet metal replacement floor pans. They are listed in their 2023 catalog. They show pans for ‘39-‘40 models.
As for a place to best ask about parts questions, I suggest posting those in this forum or the Truck section.
. My parts book lists 1939 and 40 with different numbers. Also 3 speed, 4 speed, Half ton, ton & half and COE. It lists 1937 - 38 all, which is incorrect as the ton & half have the master cylinder refill hole in a different location than the half ton. (first photo). . . The 37 cowl is straight. (Second photo) The 1941 - 46 has an inch and a quarter extra toe room. (third photo). Sorry I don't have access to measure both floor pans right now. . . .
I just measured the floor pan that I have (the one that doesn't fin in my 1940 KC) and it measures 34 7/8" side to side and 19 1/8 from the back to the base of the angle at the front edge. (So, the measurement of 19 3/4 as mentioned above by 37Blue makes sense as the measurement for the same model of floor pan that I have.)
So, perhaps the floor pan belongs to some variant of the '41-'46 models. We now just have to determine which model required the hump that is present. We do seem to be making progress and I really appreciate it!
Lou - How can the parts Chevrolet Master Parts Catalog be missing entries for models Chevrolet produced? (Not a serious question!!) But it seems that errors or omissions would have been caught over the years and corrected. The reprint I have of the Master Parts Catalog 1929-1950 would have had 10 years to collect corrections!
Anyway, perhaps someone on the forum will see this discussion and tell us what specific model(s) this floor pan will fit.
Nick The floor pan was received with my ‘46 and mixed in with a bunch of parts. It had that hump. That pan was in bad shape and couldn’t be restored, so it was junked.
I did a quick check my Chevrolet Master Parts Catalogs including editions: 1929-1942, 1929-1946, 1929-1948 and 1929-1950. Oddly, the 1942 edition is the only one that references a floor pan for the 1940, 1/2 ton KC model. It is group number 16.545 Floor Board-Floor Pan, in the ‘29-‘42 catalog.
I have photos I can email you of the pages from each of those editions, if it will help. Send me a PM with your email address and I’ll get them to you later today. I’d post them here, but the files will likely be too large given the current website limits.
As you may know, one of the challenges of working on the 1941-1946 models is that civilian vehicle production was essentially curtailed during WW2. After WW2 ended the demand for new vehicles surpassed production capacity and early ‘46 models often were assembled with parts held over from other pre-war models. One example I encountered on my ‘46 restoration was the fuel filler grommet. It came with a leather grommet, but later productions that year used rubber. My guess is the “humped” floor pans might have been used only in the early 1941 models and later models abandoned that design feature? Why it would it have had that feature in the first place? I don’t know. Maybe to prevent “oil canning”??? It doesn’t seem to have been a transmission clearance factor, at least from my experience.
Maybe someone else can help correct or shed some light on this too?
The lack of a listing for your floor pan in the Master Parts List does not surprise me, especially if you are looking at the list from a later year.
If there was not sufficient demand Chevy would drop service parts after the vehicle was older. For example, the 1928-1954 Master Parts List does not have the range of service parts for a 1928 vehicle that would have been listed in the 1929 list.
Even the 1940 Master Parts List I have had already dropped some of the 1937 parts.
. Hi Nick, . No body is perfect. If the proof reader for the parts catalog rode the trolley to work, they wouldn't catch errors obvious to the mechanic. Pix #1 is cover of 1940 parts book. Pix #2 is first page of Martin-Parry floor pans used on Chevy commercial bodies. (Passenger used Fisher bodies in US.) Pix #3 is second page of listing. You can see where it lists "1937 - 38 ALL". . . As for the lump over the U-joint, I looked in a 4X4 parts book and found a photo of the floor with a forest of levers protruding forth. Pix #4 & #5. There was no obvious lump so I looked in the GMC 4X6 parts book. It uses a Clark 5-speed that is slightly taller than the Chevy 4 speed but not where the floor lump is located. Pix #6 shows there is no power take off nor transfer case excuse for the lump. . .
Having extra or missing holes, grooves, humps, flanges or whatever is not uncommon in the world of cost driven manufacturing. The bean counters want "one part fits all" to be the mantra so they don't have to pay for expensive tooling. The question whether your panel's hump is "correct" for your vehicle is likely an answer you'll never find a definitive answer to. The world of reproduction and even OEM parts having "features" that aren't a perfect match to the original has existed for a LONG time. Looking for the "correct" part is rewarding if you're lucky enough to find one, confounding and frustrating if not. In the world of 50-100 year old cars having to make due with something close is just a fact of life. Don't dwell on humps or this or that. It's possible the manufacturer of that part put it there on purpose so they could sell it as a part to fit several different vehicles, some assembly required.
VCCA Member 43216 Save a life, adopt a senior shelter pet. 1938 HB Business Coupe 1953 210 Sedan
I think the answer is already here amongst what’s already been posted, but could benefit from being put together in one place.
To start… I think we need to clarify the origin of your (Nick’s) floor pan. A couple of things tell me it is not a reproduction, but an actual original old pan. The screw holes are the large taper formed holes for the flat counter sunk slotted screw heads originally used to screw down the pan. And, the metal around them is “pulled” and worn from use (in fact, many of holes in original pans I’ve seen are worn to the point that the original screws pull through them). One of the holes is even torn open. And, why would someone go to the expense of reproducing the “hump” in the middle when it isn’t needed?
As Rusty points out, gleaning information from Chevrolet parts books can be difficult due to elimination of listings for parts no longer furnished, or substitution of “will work” parts.
Nevertheless… starting with 1940, and excluding COE’s, all of the floor pan variations can be described and divided up on the basis of 3 things:
Years: 1940 is a stand alone year. 1941 through ’46 can be grouped together.
Truck size: ½ tons stand alone, all others ¾ ton and up are different. The difference lies in the location of the master cylinder fill hole.
Transmission: 3-speeds use different pans than 4-speeds. The difference here lies in the shape of the hole for the gear shift tower.
So: There were 4 pans for 1940: a 3-speed ½ ton, a 4-speed ½ ton, a 3-speed ¾ ton, and a 4-speed ¾ ton, and 1-1/2 ton. For 1941 to 46 there was: a 3-speed ½ ton, a 4-speed ½ ton, a 3-speed ¾ ton, and a 4-speed ¾ ton and up.
Then there is the “war production” in inventory at the end of the war as pointed out by 37Blue. I also have heard of and seen the remnants of war production making their way into 1945 and ’46 trucks, including the leather gas filler grommet on my own truck. (Yes there were 1945 model year civilian production trucks!) I think the “hump” is exactly that.
So… From that, based on the master cylinder filler location, the round tower hole, and the “hump”, I think your floor pan is an original floor pan from a 1945 or early 1946 3-speed ½ ton truck. But I could easily be wrong. 🙂
That all seems to make sense. I appreciate the clarity (and boy, do I need that) as I wade into the pile of parts that I hope will someday be a truck.
So, for now, I will use the pan I have as a template to cut a temporary plywood floorboard and hope that someone who needs a floor for their '45 -'46 will have one for a '40 and want to trade!
It is really great to have the support of this group who share their knowledge and experience.
I've been politely accused of posting about something not very important on here. This mostly happens near the beginning of a project by somebody who's not a veteran of the hobby. Being 1.5 yrs into my '45 BK 1/2 ton project, if I came upon this question, I wouldn't even consider trying to figure out what it came out of or who might want to trade for it. I'd put it in the swap meet pile & put my energy into finding the part I needed.
My '45 floor pan was rusted out. I bought a new steel one from Jim Carter. It fits perfectly. Neither the original nor the new one has a hump.
Nick, welcome the the Club. As you can see, this is quite an exceptional group. Very willing to help. An unsolicited tip; when asking a question here, you are mainly exposed to current guys who are active in the Forums. To cast a wider net, Google the question, then tag on "VCCA". This will automatically bring up all the related archives. Or tag on "Forums" to access this and other forums. Of course, use no tag & get a bunch of more stuff.
Thanks for the suggestions. I had not thought about adding "VCCA" or "Forums" to my Google searches and have been wading through a lot of irrelevant returns. This should make my searches much more effective.
I will be looking into swap meets that might be accessible from my rather remote location here in Northern New Mexico. (I have tried to connect with the closest VCCA group (2.5 hours away) but have not been successful yet.)
If you are still looking for a floor pan for your truck... and would like metal... and prefer US made ... a reproduction that LOOKS to be right is being or has been made and you can find it here:
