The Stovebolt Site Forums The Parking Lot Big Bolts 4100 frame question

How do you tell the 4100 heavy duty frame from the standard frame?
I have a 54 4100 with the original dump bed and the plate indicates a 14000 gvw. it has the heavy duty spring options front and rear. the engine is a 1954 thrifmaster not the HD loadmaster and there is no hydrovac system. I thought the hydrovac was a required option for the 14000 GVW option along with a HD frame according to orig chevy docs anyhow. 1954 4100 dump

Compare frame thickness and C channel height.

Grigg
I dont follow "compare frame thickness and C channel height" to what, to eachother? I only have the one truck and none of the specs given in any of the books that I have give dimensions of the height and width of the two types of frames. Was the HD frame just a modified version of the standard frame, IE: some type of bolted, rivited on bracing along the rail? my son and I have come to the conclusion to try to keep this truck as original as possible and we are trying to figure out if it had a brake booster on it and it was a 14000 GVW truck or if the optional suspension was added only. The 14000 tag was "put back on the truck" after the original cab was replaced due to being squashed when being loaded by the previous owner. So, if the truck has the heavy duty frame I can make an educated guess as to the original configuration and retun it to spec.
Thanks
TJM

http://chevy.oldcarmanualproject.com/chevyresto/54129.htm

The tallest part of the frame, (behind the cab) is 7" on a 4100, and 8.88" for a 6100.

Grigg
This is interesting There is a steel plate 11" tall and 3/8 inch thick rhat runs from just behind the front rearmost shackle to the rear frontmost spring shackle. the plate is formed/ bent well to the frame taper and the bolts holding it on look to be old school the cab and other attached items go through the plate, otherwise not counting the plate the frame is 7". Have you ever seen a modification like that before? the way the plate is tapered at he ends and the quality of the work seems professional. It has a Thiele dump bed made in Johnstown PA, had to be prior to 1966 to have been made at that location. The truck was assembled in Ohio.
Thanks for your feedback

I have not seen a reinforcing plate like you describe on an AD truck frame. Have seen something similar on earlier trucks though.

My guess is not factory, if it were they would have used rivets like on the rest of the frame.

Even if it is old and not factory it could look nice, there were skilled fabricators back then just as there are now.

Grigg

It was common to fish plate a frame when a dump was installed because the mild steel they used for frames would not support the concentrated load of the hoist.

Grigg
Thanks
I wonder if Thiele subcontracted with Chevy or if the original owner took it there to have the dump bed installed. What I cant figure out is how this truck was rated at 14000GVW if the only option installed was the springs. According to The chevy trucks manuals that I have it should also have had the brake booster and HD frame which I assume would be larger than 7". The GVW tag was removed from the original cab and rerivited on the cab replacement which still has the 4800 GVW plate on it as well. I do think the 14000GVW tag was original because I am the second owner and the original title showed the original GVW. Was it common to pull brake boosters if they went bad or did chevy let this one through with 14000 and just the spring option, Beats me, but I find it interesting.I guess it makes me a detail GEEK.

Hey PGH, I'm originally from Pittsburgh! I have the exact same plates welded to the frame of my 55 2nd 6100. My rear body mount brackets are bolted to the frame and not rivited, so I assume the plates were installed to reinforce the frame when they installed the dump body. It's a wrecker now, but I believe it was a dump before that. Go Steelers! SEE YA!

Cren
Thanks
It would make sense that Thiel installed the Plate, Fish plate. I will try to get some pics up of the truck and dump setup tomorrow. I just need to figure out how.
Thanks again

Hey OG, yins guy doin ok, I bet you know what a gumband is and chipped chopped ham too not to mention souside and daantaan or however down town would be written in Pixsburgese.

14000 lb is normal rating for a 4100 1.5 ton AD truck. I think brake booster was optional on the 1.5 ton, but not sure.
Do you have a bracket on the frame under the cab right side rear where the booster would have been? Do you have big vacuum lines on the firewall and under the cab? Have the brake lines been messed with and rerouted as if a booster was there?
Just some clues to look for to answer your own question.

Grigg

Grigg, here is a pick of the fish plates 54 chevy 1.5 ton frame pics

Thanks,
Yep, it's got plates on it, now what?

Grigg
Gee I thought you would think they were pretty.
Now I finnish the shop, shoud be done in about 2 weeks, then the truck goes in and starts coming apart, a little at a time.My son and I have decided upon a complete restoration, restoring it as it comes apart, not as it goes together. I could put some big old gm style rivits in the plate and stamp some ficticious GM part numbers on them just to confuse guys like yourself.
54 4100 dump

Hey PGH, Here's a couple of photos of my frame plates. I have the cab off so they are easy to see. There's one of the rear body mount bracket bolted on . They cut the rivets off , welded the plates on and bolted the brackets back on. Good luck to you and your son on the truck! SEE YA! Mark

1955 6100 frame reinforcement plates