Helper springs and model

[pfarber]

So I am trying to pick one of the frames I have to use for the Chevy restoration.

Of the three, two have helper springs, one does not. I've been all over the web and the TMs I have and cannot seem to get an answer that doesn't begin with 'I think'.

So, the SNL-G-506 says this:

Without finding the uncommon frame rail stamping, I have little to go by (but I'll check the paperwork I have... it may have a clue) it seem that NJ, NE (Cargo less winch, Cab, respectively) are all likely NOT to have helper spring? The general consensus being that heavy ended trucks (fire, dump, auger, pole setter, COE, LWB, Cab) would need the extra ass end support.

So it would be correct, by the SNL to say the following:

Cargo trucks did not have helper springs.
Other than used on the COE and LWB Cargo the rear main springs are identical between trucks
The FRONT springs would be the determining factor if there should be rear aux springs, unless the SN is known - Unless there is a winch (cargo w/w used 'hd' springs - my term)
If your frame has the aux springs your truck was one of the following:

• Dump
• Cab (tractor)
• LWB Cargo
• Telephone maint - earth borer
• Telephone maint w/w

[pfarber]

I've looked at every one of my Chevy TMs (all three ) and have not located a photo or even a reference to the aux springs OTHER than the SNL.

Also, are there any other frame 'tells' that would allow you to determine what the truck was? Like for example was the 5th wheel on a tractor on its own unique cross member?

[pfarber]

I spent a few hours looking over the Chevys and there are some things that I have to question. Namely that cargo trucks didn't have auxiliary springs.

I see several possible reasons why a cargo truck would have springs:

Most cargo trucks with aux springs have the stops bolted on. Every other frame mount is RIVETED. If the trucks had aux springs from the factory, would they not be RIVETED also?

Could there have been a field mod that required that installation of aux springs and stops to help with cargo tucks load capacity? It's common knowledge that CCKWs have had some major field mods (deep sump oil pan, die cast carb air cleaner support, crankcase ventilation) applied post factory/in the field. Why would the Chevy be any different?

If most of the trucks with aux springs were dumpers, then wouldn't there be some other frame/cab mods to accommodate the dump configuration? Like brackets for hydraulic pump operation, cut outs in the floor pan for levers, some items moved to accommodate the dump body/config?

Just thinking out loud.

[pfarber]

Well here are some photos. Of course I have three chassis, and none, from what I can tell, have been dumpers.

First, the wooden cargo body truck:

Registration has the SN as 8NJ2819XXX

This decodes to:
Built in Atlanta, GA
It was originally a cargo, less wench (NJ)
Built in March, 1943
It was the 19,XXX truck (Yes, there is a debate on the 4 vs 5 production sequence)

Here is what the rear looks like:

Note that this frame has auxiliary springs and BOLTED on stopper. Here is what the floor pan looks like:

Note no cut out for a winch or hoist control.

Kinda makes sense that the auxiliary may have been a FSMWO to increase load capacity/protect the truck from frequent overloading.

[pfarber]

I have no information about this late 41/very early 42 chassis. How do I know its an early truck?

The cab rear window:

Screws in from the inside an there is a pot metal retainer on the outside. The gas tank support also fit the early style.

Here is the ass end of the early truck:

No auxiliary spring or helper. Or holes thereof. Looking at the floor pan, also, no hoist controls.

[pfarber]

Next we have the enigma. I have no idea what the SN is, but from the stuff that's on this it it looks like a typical 43+ model cargo, no winch.

Here's the ass end:

There's all kind of things going on here. Auxilary springs, the stops are WELDED on, in the proper location, and there are no bolt holes in the frame. The spring hanger mounts are also 'beefed up' with a welded gusset.

Here is the floor pan of this truck:

It currently does have a dump body, and the levers do actuate the hoist. It looks like the initial cut out for the levers was 'clean' then 'stretched'.

I don't want to say that this floor panel is an original hoist cut out style... but it looks like there was a clean cut hole to begin with.

[pfarber]

So what does this add?

Well, would a post war truck owner have access to the parts to add on the helper springs in the quantity that we see them on trucks now? Were dumper/fire/telephone maint that large a portion of the production that they would outlast all the other models simply because they were so numerous?

I'm really leaning towards the 'they were added as a field mod' explanation. There should be a list of all FSMWO's for the G506 somewhere... right?

[pfarber]

Well looks like there is an actual photo of the auxiliary springs in the TMs (well, of the 3 G506 TMs I have)

TM9-805 page 7 has a side shot of a G7106/G-7107

You can make out the auxiliary spring stops. Here it is:

Note the lines. I tried to make them level with the TOP of the auxiliary spring stop. Look at how high up on the frame the front stop is.