How are they different? I don't see a fifth center hole.
Look at the way the bumpers are shaped compared to the center photo of a new replacement bumper, they are not shaped the same. The one pictured on the truck has a couple extra things, accessory guard and a third bolt on the end which are not needed.
I will have to look in my stash. My frame that came with many other parts was a GMC 1 ton. I think I may have the bumper for it. I am using a chevy nose, hood and grill so I won't need the bumper.
Give me a couple days.
Chris, let me know, the 47 and 48 GMC 1 tons would have come with that same odd looking bumper, it is different from the Chevy bumper used that same year. Also if you happen to have a bumper bracket shaped like a question mark, I am looking for one of those as well.
The 47-48 bumper has rolled edges top and bottom. Chevy bumpers and repops are almost flat top to bottom. The 47-48 bumpers also takes a special set of brackets to accommodate the different grill and support bars that go with it. I have a 47 and a 48 but do not have an extra bumper or brackets. Keep looking, the hunt is half the fun.
Twin Jimmys, the front brackets on the 3/4 ton are also special in a different way because they look nothing like the 49 and later brackets. I actually found some NOS ones on E-bay recently. The 3/4 ton brackets sit forward a lot more, and are held on by only 2 bolts where the later ones are 3 per bracket. They are also shaped differently. I have both outer brackets, but I am still short one inner, it's shaped like a question mark. I found a springs and overloads shop in Salt Lake City, Utah that can probably make the bracket I am missing but I am still waiting on a call back from them to see if they can do it.
Ryan, That bumper was used on 47, and 48 model series 100 1/2 tons, through series 250 1 tons. Series 280, 1 1/4 ton, series 300 1 1/2 tons, & series 350 2 tons, all used the heavier channel bumpers. No 300 series 1 1/2 ton trucks used that bumper.
Thought I'd also mention that I am looking for a set of rear bumper brackets for a 3/4 ton as well. Yeah I know there are new available, however I do not want new.
I found the bumper I was looking for finally. I guy in a different forum had one.