The reasons for having a rear bumper on a TJ are 2. Looks and to put stuff on. Because of the position of the spare tire it doesn't do much good for a bumper's original intent - wrecks etc. So, what do you want, looks or usefulness or both? A very heavy angle iron makes a good bumper - flat side against the cross member and other angle on top. Attach to cross member as well as frame. Cut holes in the top flange to attach D rings. Cheap, strong, usable. Looks? well......
Whatever you do, if you intend to off road, the closer the very back of the bumper is to the back of the Jeep and the higher it is, the greater your departure angle will be. If you want a receiver hitch in it, try to get it mounted in the center of the bumper, not on the bottom - better departure angle, but makes regular trailers look funny - tilted up in front.
Attach it to your cross member using big washers on the back side of the cross member or a big flat piece of 1/8" or 3/16" steel - one piece behind all the bolts. Then attach to the frame ends and put your tow points as close to these connections as possible.
There are several good bumpers on the market. Actually you can just duplicate a stock bumper with the end caps removed, but make it out of much heavier channel iron and attach it firmly to the frame and reinforce the cross member where it connects.
First impressions with a new vehicle are to buy stuff that is already made for it. You can do that, but you can also make stuff for a Jeep fairly easily and save lots of money.
Have fun and happy Jeelin'
Doug '97 TJ
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