The Stovebolt Site Forums The Shop Area Paint and Body Shop Rear Bumper Brackets on 53 3100

Could someone please tell me, do the rear bumper brackets bolt to the inside the frame or the outside the frame?

I have tried them both ways and neither way seems to match up with the bumper holes, too wide on the outside and too narrow on the inside.

It did not have a stock rear bumper, so I purchased a reproduction bumper and brackets.

I'm thinking I may have to bend the the brackets a bit to make them fit, but want to be sure I have them on the proper side of the frame rail before I do that.

Thank You

Install the brackets onto the bumper first, leaving all the bolts loose. Then see if you can get the brackets inside/outside of the frame rails. If so then tighten everything down. Good luck.🛠

Outside. See sect 14, sheet 1.01 of the factory assembly manual.

Lynngrove, I am having issues with my front brackets on my 37. Ordered new brackets and bumper from chevs of the 40's. I have tried to install both ways, on bumper then on truck, on truck then install bumper and nothing works. Have been waiting for 3 weeks for a answer. To me the brackets are not bent correctly. Good luck. Bill

Thank you for the replies.

Martin, I am going to try your suggestion this weekend.

Gord, I saw they were on the outside in the factory assembly manual before I tried putting them on the first time. But the distance off is the worse when the brackets are outside than inside. That's what puzzled me.

Bill, I'm thinking the brackets I have are not bent correctly. I want to try a bit more before I come to that conclusion.

Thanks Again!
Tim

I have a '49 with them on the outside, and a '50 with them on the inside. both of them have original brackets. While there is a "right way", they can go where they fit the best using Martin's method.
If one is a purist, that horse has already got out of the barn with the aftermarket parts.

Jim Carter has some tech articles on Advanced Design Bumper.

You might have a front bumper and or panel truck bumper braces.

Advance Design Bumper slow to load

1947-1955 Rear Bumper Braces slow to load

Hard to believe/observe that JC misspelled Advance-Design?

A photo on his website, of course, has it right/correct (see image, below).

By golly you're right !!

Good catch, at least your eyes are still working.

Dully noted & changed my post to correct Advance-Design.

Here is another reference to Advance-Design that you might like, jorb

Some people have found a few GM sales documents with illustrations without the dash between Advance & Design (I attribute this to artist-error). I have never seern a GM technical document with Advanced-Design.

Some good stuff there, Tim

Me nether, but I can see how a person can say it incorrectly.
I think it has something to do with the word Advance itself.
Advanced seem to roll off the tongue easier.

But than again like Sargent Schultz use to say "I Know Not-ting"

xfiles

Well, the design might have been an advance back in the late 1940s, but now we think it was an advanced design for it's time.

Back to rear bumper brackets. I'm contemplating making my own as I would like the bumper to be a bit closer to the back of the truck. Should be easy to get some 3/8" x 1 3/4" flat bar and bend to suit.

The original brackets are made of spring steel (don't know about the repops), but plain ol' mild steel flat stock will be pretty soft and bendable in the instance (heaven forbid) of a rear-ender.

Are you sure that they are spring steel? I had to bend them into shape when I installed the front bumper.

Our front bumper was bent. The chrome shop straightened and re-chromed it. I had to deal with the brackets. Clamped a long piece of angle iron onto the bracket and gave it a good pull to get it back where it should be. (lynngrove may have to do the same)

My brackets were broken in a couple of spots, which typically wouldn't happen to mild steel. Spring steel will bend to some extent, but exhibit quite a bit of rebound, and if bent too much, will eventually fracture.
I have the pieces of mine in my scrap pile, and can try bending them, but I'll lay money on it that they're spring steel. A high carbon steel will also exhibit a different spark pattern than mild steel if you use a grinder on them.
Here's a couple of links on spark testing. Spark Testing 1 Spark Testing 2

Please don't bother on my account. I will have to go with mild steel as that's the only stuff available to me.

This afternoon, I tried Martin's idea of mounting the brackets on the bumper first and then see where the brackets fit the frame rails.

The brackets ended up being close enough that I could start the bolts and then tighten them down to pull the brackets into position on the bumper.

The splash apron (CounterPart) on the other hand took a little bit of work. Apparently the two tabs on the left side were not welded to the apron in the correct positions, they were about a half inch too far toward center. This resulted in the slotted holes not allowing the apron to center with the bumper. Luckily the tabs were wide enough that I could drill a hole and use the jig saw to cut the slot further in the proper direction.

The brackets, apron and bumper then bolted together as they should.

I did not have any help today, so I could not mount the bumper on the truck. Measurements indicate the brackets will fit snugly on the outside of the frame rails.

I did clamp a piece in the vice and tried bending it, but I didn't have enough leverage, even for mild steel. But I did do a spark test with the grinder. Definitely not mild steel.

Hope the mild steel works out for you.

I admire your patience. I probably wouldn't have waited for help and tried setting the bumper on jack stands and lifting the brackets up into place. Of course, the bumper would probably fall off the jack stands resulting in some (ahem) frustration.

@Kevin: I will let you know how it goes. Looks like a Springtime project.

My nephew stopped by today and helped me install the rear bumper assembly on the truck. The brackets fit nicely on the outside of the frame rails (just a little minor prying with a large screwdriver). Once it was slid on, the buttons on the rivets popped into the holes in the frame and held it there while I installed the bolts. Bumper and brackets fit well and look good.

The CounterPart splash apron, not so good. It already had the issue with two of the five mounting tabs not being located correctly, that I had to fix yesterday. Today I discover it is not bent correctly to sit flat on it's own, so the edge of the apron (away from the bumper) angles down, more on one side than the other. It needs some of spacer between it and the brackets, near the truck frame, to hold it up and level with the truck bed. The bigger issue is the curved pieces on the sides, that are supposed to fill the space between the bumper and the back of the fender are about an inch too short. There is a full inch gap behind each fender. I am going to take it off and fabricate something, which I should have done in the first place.

Thanks again to everyone who replied.

Reproductions...

Everyone’s stories are eerily similar. They just suck. Hence, why I’m still fighting with my original door on my C10.

1947-54 Factory Assembly Manual

R.P.O. 218 Rear bumper instruction (attached)
Section 0 Sheet 5.00 LINK

R.P.O = Regular Production Option

xfiles

Well it's almost Spring and I'm back. It went well, IMO.

Here are some pictures. The brackets are made of 2x2 square tubing and 2x2 angle. The holes in the square tubing are used to attach the brackets to the truck's frame. The holes in the angle are used to attach the chrome face plate.

Nice Job

The square tubing will be pretty stiff and up to the task. Kind of like doubling up on flat stock.

Thanks. My original thought was to use flat bar. When you start sketching things out things can change. That's normal.

That 2x2 is skookum. I think it would be easy to add a piece between the two brackets for a trailer hitch. (except I don't want to tow anything - I have a newer truck for that)

Rear apron was not O.E.
Fabricating something good idea

For my front and rear brackets I used extra long bolts held loosely to start all the holes, then drew everything up. Once made up swapped out the long bolts one for one.

Still needed to use a ratchet strap on front brackets.