I saw a thread on ford trucks and thought it might be useful to some of you guys for a similar thread. I thought we would start with the 1/2 ton pickup. the 1939-46 chevy truck has a lot of parts at first glance look the same but in fact are not. i am a big fan of the 1939-40 truck which to a lot of guys is the same truck but actually has quite a few things that are not easily interchangeable. i think probably the best place to start is the cab differences. i am sure i dont know all of them and please feel free to add any i missed or have incorrect. The 39 dash was a thin flat plain panel that used 37-39 gauges. the windshield crank stuck straight out of the dash. the rear window is in a piece of rubber that is sandwiched by an outside ring that bolts from the inside. the passenger door has the external lock in the handle. The firewall is straight up and down with the strengthening beads running vertically. i also found this last weekend there is no drail holes at the bottom of the windshield opening. The 40 cab is similar with the exception of the dash is thicker , more rounded, and used a new designed cluster that had all of the gauges in one package instead of separate like the 39. The windshield crank is more vertical and comes out of the top of the dash instead of the front. the rear window mounts the same and the doors, door handle/locks are the same. as is the firewall. They did add the windshield drain holes to both sides in this year. The 41 cab started to change a few things. like the firewall, it was stepped out 1 1/2 inches for a bit more leg room. the firewall strengthening beads are in a criss cross pattern now. The cowl vent linkage and handle are really different than 39-40 the vent also operates a lot smoother. the door lock is still on the passenger side but moved to the door sheet metal like the car. i believe the lock cylinder is the same car to truck. the rear window bolts in the same, dash is the same as are the gauges. The 42 ( i think) they changed the rear window to a rubber pinch weld design. all other things are the same. There maybe other changes but i have only looked at (1) 1942 truck and not really close. the 46 i am not aware of any other changes in the cab from 42. Next i will go into the front sheet metal which is always a fun topic on these trucks.
pics are worth a thousand words so i thought i would add a few pics of the differences in the firewalls that i was talking about in my last post. the purple truck is a 40 and the other is a 46
I am glad it helped you. i am going to get some pics together shortly on the differences of the front ends especially the difference between a 1939 and a 1940. i see the radiator support/ grille shells advertised all the time as the same and they are not.
i am going to start the front sheet metal discussion with the difference 1939 to the 1940. the first pic is a 1939 radiator support, the upper trim bar only goes back about half way to the hood. the piece in between the trim and the hood is part of the rad support and not removable without cutting it off. the second pic is a 1940 radiator support, the trim bar wraps all the around to the hood on both sides and is removable. i see a lot of 40 fronts described as fitting 39 & 40 which is not true. the complete assembly is interchangeable but the individual parts are not. I.E. a 1939 upper trim bar does not bolt to a 1940 radiator support. the front of the radiator support is also a little bit different shape so just adding a piece between the trim and the hood doesnt make a 40 support into a 39. The problem with the 39 supports and upper bars are they are a bit fragile and easy to break the upper mounting tabs off. the upper trim bar has no support in the center and most have been broken in two and welded back together. the grilles are close to same with the difference being the 39 has 17 bars and the 40 has 16 bars. you can use a 39 grille in a 40 by removing the top bar. the v bar from the cowl to the radiator is the same between 39-40. the the brace above the radiator that the v bar attaches to is the same 39-40 other than the 40 has a strength bead rolled into it. The headlight buckets are physically interchangeable but the 39 has reflectors and bulbs and gm went to sealed beams in 1940. the front fenders and hoods are the same on a 39-40 but the parking lights were moved from inside the headlights on a 39 to a fender mounted park light on the 40 which i believe is the same light fixture as the car. the easiest way to tell if a front fender you are looking at is a 39 or 40 is by the mounting holes for the parking light or lack of holes. The inner fender is also interchangeable from 39 to 40. the hood handles are the same from 1939-46, but the hoods are not. also the cowl differences from 39-40 to 41-46 the front sheetmetal from a 39-40 isnt a direct bolt on to a 41-46 cab because of the hood latch system.
Those hood handles are used on many of the '30s GM cars as well. I was always able to grab a chromed pair from a Chev Master or Pontiac. The '41 truck parking lights were factory equipment on '40 Pontiac, and most, if not all were partially chromed.
Thanks for the info: have been looking for a 1940 1 ton or larger for a while. My grandfather had one on the farm.
The Stovebolt Page has a good tutorial on 41-47 trucks. https://www.stovebolt.com/techtips/art deco/index.html Not all inclusive, but useful.
More info please, running boards, rear fenders, bumpers info please Sent from my iPhone using The H.A.M.B. mobile app
Is there a difference between 39 and 40 rear fenders and beds? Sent from my iPhone using The H.A.M.B. mobile app
yes there is. the bed is narrower on a '39 by 3 inches than a '40-'46. the rear fenders on a '39 are 1 1/2 wider to make up for the difference. the skirt between the frame and the running boards are also different because of the box. the rear fenders on a '39 are probably one of the hardest fenders find in any condition. i have one set that i am trying to fix for my current '39 project.
I’ve always liked those taillights and wondered why more people don’t use them on customs. They’ve gotta be getting hard to find now. Nice job...... Sent from my iPad using The H.A.M.B. mobile app
i actually bought the remains of the quarter panels and lights at a swap meet and didnt know what they were from or what i was going to do with them. i decided i wanted a custom box for this truck and they fit what i was going for. i have lucked out and found enough lights to make a nice complete set of 4. most of the time the guys i have bought them from didnt know what they were for. it also helps that the reverse lights are the same housings as the tail lights.
...some of the war year trucks (41-5) used tin door handles, 2 peices of formed tin pressed together...
^^^^^^ And painted gauge cluster and dash trim, with a leather skirt around the gas filler in lieu of the rubber used until '41 ...
Going back to the front, is the chin under the grille the same on a 39\40? Also, how about the running boards from 39-46? Sent from my F-10XIPS using The H.A.M.B. mobile app
The chin is the same on 39-40 trucks as is the baffle from the chin to the support. i am not sure on the running boards. i think the 39 is different than the 40-46 but i will have to measure them when i get a chance.
the running boards are the same from 39-46 according to the measurement i did over the weekend. finally got the 39 back in the shop.
The 41 door lock is still in the handle, it switched to the door in 42, also it seems the majority of 41's only have one wiper but nearly all 46's have two.
i have had some 41s with the lock in the door so i am wondering if it was a running change? the 41 cars had it in the door on both sides
Stoked I found this thread! Its a gooder for info. I have some questions Will a '39 / '40 GMC hood fit a 46 cab cowl? Not worried about the latch as it will be kustom. Or can a '39 or '40 grill work on a later hood? Again its a kustom build. Where can a guy find parts? Tailgate, grill, tail lights... -Shiny
i am glad you like the thread. the 39-40 hood should fit the cowl on a 46. the 46 hood is a bit longer than the 39-40 hood, i dont know if the shape at the front of the 46 hood lines up with the 39-40 grille. tail lights are available new if you want stock type parts. they do repop grilles and tail gates i have not tried them so i have no idea how well they fit but if you are doing something custom that may work for you. other wise i just buy everything i find at the swap meet which these parts are getting to be less and less.