OK....this will be a lot to take in, but hopefully it is helpful for you or anyone else looking for info about the rear tube bumpers.
Firstly, the bumper that I have in it's original box (NOS / OEM) is date stamped "88" on the ear of the box, and the molded in date codes on the back of the plastic license plate bracket shows Dec. 1987, and the part number shows 8-31-87 (part #E87J-13406-BB B-10).
Overall, the tubes and brackets look to be the same as what is on my truck (came from the factory with the rear tube bumper), but my truck was built in early 1987 (I have owned it since 1992, and knew the previous owner who had it for two years prior), so for reasons unknown to me, the license plate bracket is drastically different. The one on my truck has a metal plate that has the lights in the bottom, with a short bend up at the back to attach the plate to. The "new" bumper and brackets/license plate mount are all directly from Ford....I have the original box, and until today, the inner box that had the brackets in them had never been opened and was still sealed from Ford. My guess is that they superseded my '87 OEM-style with this other style....but maybe someone out there with an '88 could corroborate that.
Since this is the first time that I have tried to post things on The Station, I will upload pictures as I figure out how. I took a total of 60 pictures today of the "new" bumper and my super-swiss-cheese oem bumper that's sort-of still hanging on my truck (Southern Illinois and Minnesota winters killed it, along with the floor pans, cab corners, etc.) Also, disregard the bolts and screws through the step plate on the old bumper. I drilled those in back in 1997 when I pulled out an F-150 stuck in the mud....using the trailer ball....which was promptly separated from the bumper, along with pieces of said bumper (I was young and dumb).
I will try my best to type out the measurement descriptions, as well as upload a terrible sketch with my notes. All of my measurements are taking into consideration the actual metal before powder coating, and not including the plastic end caps. I also have scans of the included original mounting instructions/parts list. I did not sketch out or measure the included frame adapter brackets. If you want me to get you info on those, let me know.
Here goes.....
Tube wall thickness: 1/8"
Steel bracket thickness: 1/8"
Tube O.D.: 3"
Bottom tube overall length: 60"
Each top tube overall length: 19 3/4"
1" space between upper and lower tube.
Step plate is 17 1/2", measured straight across at the upper ears.
Step plate is 3 1/16" wide, measured flat across where the trailer ball hole is.
Trailer ball hole is 3/4" (rubber plug inserted from Ford).
Step plate is flat riveted onto the lower tube (rivets are under the adhesive tread steps)
There are also welded-in plates with threaded nuts on the inside ends of each of the upper tubes, in order to bolt on the license plate mount. The OEM bumper on my truck does not have those, since the license plate bracket mounts from underneath. Mine originally had plastic caps on the inside of each upper tube.
The two holes in the bottom of the bumper to mount the plastic license plate bracket to are 7" O.C.
The trailer chain loops are welded at 19 1/4" from the end of the bottom tube, to the start of each outermost weld.
The trailer chain loops are 3 1/2" wide each, and are 2" wide at the "loop", with a bend distance of 1 1/8" from the tube. The look to be made from 1/4"-thick solid round-stock (no way they are ever stopping a run-away trailer....those flimsy loops and welds would get yanked off immediately).
The trailer chain loops are welded on the back of the bottom tube (towards the truck), but are tilted down some. On the OEM bumper on my truck, they are welded on the front of the bottom tube (towards the trailer), but are also tilted down some.
The small outer supports that are welded between the uppers and lower tube are 1"h x 1"w (roughly, since they have a soft 90 degree bend) by about 1 3/4" tall (they have really ugly factory welds, so hard to tell for sure). The single hole drilled through each bracket (where the supplied 45 degree arm mounts to the frame) is 7/16" diameter.
Each of these small outer supports are welded in at 5" from outer end of the tubes.
The main mounting brackets that are welded to the back of the tubes have a soft 90 degree horizontal bend at the top, and the brackets are notched to fit up against the backs of the tubes, with a section left in that is welded in between the tubes. The overall vertical height of the bracket at the back is 3 9/16". The horizontal piece (bend) is 1" wide. The holes in that bracket are 1/2" diameter.
The mounting holes in those main welded-on brackets are offset diagonally, with the upper holes closer to the truck at the top of each bracket. The distance from the back of the bracket face to the start of each hole is 1 3/4" for the bottom hole, and 3/4" for the top hole. The distance up from the bottom of the bracket to the bottom of the upper mounting hole is 2 1/8". The distance up from the bottom of the bracket to the bottom of the lower mounting hole is 1 3/16".
These main brackets are welded in at 13 1/2" from the outer end of the tubes.
I'm sure that I've not included everything needed for someone to fab one of these, so let me know what other specs to supply.
Best of luck to everyone, and thanks for being a part of the great Ranger Community!
Shane B.
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