Pictoral differences found on G4112 vs G506 (more images)

[Joe Gopan]

Hello all,

I hope the images were fun to view.

The serpentine grille and Chevrolet embossed side panels were not exclusive to G4112 trucks. 1942 G506's had both of those items up to approximately June 1942 (would like some input on nailing down that exact date). Blackout driving headlights were not installed at all on early trucks, as the wiring harnesses lack the circuits, and the grill guards lack mounting holes. I think BO headlights were a depot addition on some vehicles, and true the early brackets seem to be mounted high.

Good eye on the voltage regulator, it is an Autolite. Mounting holes are evidently the same. How a Dodge part found it's way on a Chevy is a blasphemous mystery. It will be changed.

The firewall on the G4112 is as simple and uncluttered as these Chevy's get, so I can easily reconstruct to original.

I am still not convinced that the early trucks had functioning ash trays. I have seen 3 apparently original G4112 trucks, and they all have the ash tray front, but it is just used as a cover for the hole in the dash. As smoking was a common activity post war, I think that many early trucks were retrofitted with civilian ash trays after they were decommisioned. The dashboard has everyting there to bolt on a civilian ash tray bracket.

I am not sure about the hand brushed red paint on the interior of my truck. At first I assumed "firetruck", but it is only on SOME parts of the interior? None of the exterior has red paint with the exception of the hubs. I am now inclined to think it was some more random act like "hey bubba, get some of that red paint from the shed and go paint that Chevy" and perhaps nothing more. Another mystery.

Paul

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The 6 V0lt 40 Amp VRY Neg Ground Series Autolite are an approved WWII replacement for the 6 Volt Delco 40 Amp Neg Ground Voltage Regulator. The swap has been encountered since the WWII Days.

[kelley]

Merry Christmas Paul,

Thanks for putting this together, Here's my limited contribution...

Truck was built at Oakland in 4/42, non serpentine grill,has Military instrument panel,no ashtray, no data plates on the glove box door. The drivers door has no lock the passenger door does.

My truck, up until recently has had a long hard life. It had many, many coats of house paint on it and dozens of extra holes drilled, cut and rusted into it.

So who knows how reliable this information is.

If i lived closer i'd be happy to come over and help with your truck.

Kelley

[MChapin]

Paul- Thanks for the picture. Your serpentine more than likely is correct, as the truck does not look to molested. As near as I can tell I am the 3rd person to start a so called restoration. A lot happens in 70 years. I have been slowly replacing parts I did not feel were correct, thanks to the information provided here. Any one have a serpentine grill?

[M38CDNBill]

Hello Paul,

Thanks for these informations. I learned new things about the G506.

Cheers

[retro-roco]

Any one have a serpentine grill?

Yep. My June '42 truck has one. No sign of ever having a blackout driving light...

[forestry4evr]

This thread has sparked some good disscussion, great!

From our very limited survey of trucks, it seems as though the last dates for trucks having serpentine grilles is holding relatively true to about the June 1942 date. There are exceptions that are not totally explainable. I suppose as these trucks were surplused back in the 1950's some companies bought numerous trucks and maintained fleets for business. Fleet mechanics often see parts as "fits or doesn't fit" and subsequently swapped parts as needed. Also as the trucks aged into the "beater stage" probably in the 1960's+, the trucks were used hard for various utilitarian purposes with little regard for historical correctness. As old 4x4's are often repurposed over the years things get muttled. I know I have made 4X4 trucks for farm use or woods trucks and once you get one, other ones "follow you home" for parts/pieces. As they are made for a specific utility use, absolutely no effort is made to keep them original, you don't expect them to survive. Now that these trucks have become antiques, folks are looking at the components more closely than ever before. Just my theory.

Ronnie and Mark, you guys may want to swap grilles?

Kelley, you have done great considering what you had to work with. Thanks for your input, as it seems period correct with the exception of the grille. Your truck looked to have been highly altered though so it is difficult to tell. I am glad that you decided to make a bumper instead of bidding the farm on that eBay Idaho bumper. I didn't think I could outbid you and you about broke me, but it is one of those unique G4112 items. It has all of the original rivets, and is in relatively good condition. It has a different mounting system than the G506. The bumper is one of the best Christmas presents I could ask for, fortunately "Saint Lawrence" made it happen.

Joel, so the Autolite voltage regulators were used in retrofitting to 40 amp while in service or was it fitted after the vehicles were decommissioned? The mounting holes on the firewall match the 25 amp Delco. Were these voltage regulators used in both Chevrolet and GMC trucks, and was it common?

The 6 V0lt 40 Amp VRY Neg Ground Series Autolite are an approved WWII replacement for the 6 Volt Delco 40 Amp Neg Ground Voltage Regulator. The swap has been encountered since the WWII Days.

What does "VRY" mean?

Kurt, it is interesting that your June 1942 truck DOES NOT have holes for a blackout driving light. Is there any evidence of grinder marks or metal ghost marks where someone filled the holes? Upon closer inspection as I was taking my grille off for engine removal, I mis-spoke in saying that my G4112 grille had no holes. It does in fact have the holes, but there are no wiring circuits. I guess the hunt for the bracket, light bucket,and wiring retrofit begins. Always something on the shopping list.

Thanks,

Paul

[42cargo]

Hi Paul,

Good discussion. My July '42 has a straight grille, with a high-mounted blackout driving light. Regarding the latter, the blackout driving light frame that came with the truck was actually a very early horse-shoe type, which would not have been correct for this vehicle. I've since changed it out for the correct type with the dip in the back. My guess on the original set-up was that someone either added it after the war as part of a "restoration" or that it was a war-time field mod.

Regarding Kirk's grille not having any mounting holes, it could well be that his truck never had a blackout driving light, or if it did, it might have been mounted on the fender late-war style as a field mod. Again, just guessing.

John

[Joe Gopan]

BOD retrofit Kits for the various early wheeled vehicles without them were issued starting early 42. The G-506 Kit would be the same as CCKW Kit, production BOD Guard was incorporated into symmetrical G506 Radiator Guard at the extreme low point.

[42cargo]

Here are some shots of the early- and late-war blackout driving light frames:

Click on thumbnail images to get larger versions


Early-war


Early-war, mounted on grille


Late-war, fender mounted


Late-war, fender mounted rear view


This was the field or post-war modification that was on my truck. That horseshoe frame has found a home on a '42 GPW.

[Ronnie Guin]

I will keep my serpentine grille on my 11/42 G506. It might be like the GPWs that had script tubs show up in later productions than were first thought due to tubs misplaced or laying around in storage?

My frame and data plates match and the engine block has a rebuild tag on it that says P.O.D. Base Pueblo Colarado date 2/53

[forestry4evr]

Does anyone know when the later version low mounted blackout headlights began being used? Are the correct BO brakets for Chevys only used on the G506 and G508? Are the BO headlight buckets the same for other WW2 vehicles, and is there a suitable reproduction part out there?

In regards to the grilles, I imagine that some relict parts did get put on later production vehicles. The vintage images of the assembly plants has always amazed me as vehicles of all sorts were assembled one after the other in the same line. Bolt on a 1/2 civy pickup wheel, then next bolt on a 1 1/2 ton g506 wheel; it is a wonder that more errorors didn't occur. On a parts truck I have, the right lower engine cowling is attached with 1/4 clutch head screws while the left cowl is fastened with slotted screws yet both look as though they are undisturbed from the factory.

Ronnie, I don't blame you for keeping the serpentine grille, I think they are a subtle expression of the Art Deco period on a military truck. I have to admit that I am very biased in my opinion.

Paul

[kelley]

Hi Paul,
The windshield post to cowl connection on my 4/42 cab is soldered. The same connection on this 2/45 cab is gas welded.
HAPPY NEW YEAR!

[forestry4evr]

Hello all,

I trust you all were good little boys this year so Santa Clause left you many great Chevy parts under your Christmas trees, or out in the yard in the event that they were large or greasy presents. I must have been good as I have been blessed with many needed parts.

I finally got the SBC sold and out of my truck, things are moving forward! The sale also helps fund this Chevy addiction. I have removed the front clip, so the truck is not really looking much like a truck anymore.

While working on my Chevy, I noticed a couple more differences in the early trucks. See below.


The crossmember for the radiator support has simpler bends on the G4112. At first I though it was a modification as it was bolted not riveted, but it has factory edges and elogated holes (attaching bolts were fine threaded military and were welded to the nut, not sure why it was removed as there is no frame damage)


Radiator support members on the G4112 have sharp right angles versus a radiused edge on G506 trucks.

Kelley, a friend brought to my attention the lack of solder on later trucks. I really don't know when they dropped the "finishing touches" on these trucks, but feel it was somewhere in 1943 (can anyone confirm?). I suppose the war department determined that a rough gas weld at the pillars was okay. I have been told that the war time life expectancy of ww2 vehicles was about 4 months.

I hope this year was a good one for you all, and that the next is even better!

Paul

[forestry4evr]

I was welding tears and removing "bubbafications" on some dashboards yesterday and thought I would post some more differences that may be of interest. Enjoy!


Green dashboard is from a ca 1942 G506 truck, white from a late 1940 G4112 truck. Notice that the white dashboard is nearly identical to civilian models right down to the chrome trim with the exception that the center windshield crank stamping is not drilled out.


Differences in the dashboard stamping and control locations


Push-pull light switch is located to the left of the steering column on the g4112

[forestry4evr]

Last night while tearing down my doors, I did a little investigating. I think I found conclusive evidence that the passenger side door handle is in fact military and most likely original to the truck. If you recall, outside lock mechanisms are only found on the 1940-41 YP and ZP model G4112's, and only on the passengers side similar to civilian trucks in 1941. Now to find a locksmith that can make a new key, can anyone offer any guidance?


Notice OD paint remaining where protected in door, and same style handle as civilian but without chrome plating


Passenger side door handle with lock mechanism


Number found on handle.