I stored my hose in the bumper for years and just this season got the 5" PVC fence post to store it. I have never had an issue with the bumper caps falling off, but the 4" bumper is barely big enough for the hose, let alone the fitting. The end of the hose with the bayonnet fitting would have to go in cocked so it would fit, and with the inside of the bumper rusty from storing the wet hose, if it got stuck it was a bear to get looses. Not to mention the abrasion on the hose from sliding it in/out of that rusty bumper. Plus the rust stains on your hands. Plus, I had no where to store the elbow fitting (on the left in this pic):
The other thing for me is that I needed to add extra tail lights when I extended the frame, and putting all the wiring in the bumper made everything nice and neat, which meant finding another storage place for the hose.
