Christmas came a little early this year with the delivery of my new Rock Hard Rear Bumper System. It was well packaged and there was a small mountain of bubble wrap on my garage floor by the time I was done.

The one drawback I was warned about by my friend Danny from Southwest Off Road was that even though this was a very well designed and built bumper system, the instructions were really poor. That guy from Rock Hard 4x4 can build, but he can't write instructions to save his life.

The first thing to do is the demo. You need to remove the spare, spare mount, rear bumper, trailer hitch receiver and anything else you've attached back there. In my case, I tried a Hi Lift mount on the bumper. I found it to hang down a little low for my comfort level.

I fear no holes I've drilled because of my secret weapons, POR-15 products. This particular filler is made specially to chemically interact with rust and stop it in its tracks. It also seals out any moisture that may want to sneak in and spoil our fun. Use some kind of latex gloves, or you'll be wearing that stuff for days and days.

Once you get everything off from back there, take the brass colored striker and the black nut with the tab welded to it. The striker goes through the hole to the left of the rubber pad on the left top of the bumper. Thread it into the tab nut you've placed inside the bumper corresponding with that hole. Snug it in but don't tighten it yet.

You'll notice there are four holes drilled in the rear frame cross piece. Take the two long hardened bolts (you can identify them by their brassy color,) matching washers and lock washers and push them through the two center holes so they are pointing out rearward.

At this point you're going to want a strong bud, or a long reach floor jack hanging around. This bumper is built to last and the weight of it is a dead give away of that. [IMG][/IMG] The entire kit is built with very tight tolerances so be ready to do some pushing and pounding to get everything on right. As you align and push on the bumper, get those two bolts you placed sticking out the back of the frame started. Don't tighten them yet. If you don't do it now, it will be impossible later on. You may have to use some rather large persuaders to get everything just right. Remember, if you're using metal hammers, to place a block of wood between the hammer and the object you're pounding on. That big rubber mallet sure came in handy.

Once everything is aligned and the two center bolts are started (but not tightened), then thread one of the bolts you removed from the side brackets of the plastic bumper back through the top hole of the side bracket and into the frame on each side. I know this picture shows both bolts installed, but wait for the bottom bolts for a bit. [IMG][/IMG] Using your persuaders, get everything lined up just right, then find two bolts from the parts kit that are slightly larger diameter than the side bumper bracket bolts. Grab the corresponding washers and lock washers and install them. They also go on the side bracket, but they go in up close to the bumper itself. It was impossible to to get a picture, but if you reach your hand up in there, you'll feel the hole. Again start the bolts in (one in each side,) but don't tighten them. Once all of the bolts are in, tighten them up. First tighten those two hardened bolts going through the rear frame, then the two bolts from the old bumper bracket and finally those two bolts on the side up close to the bumper.

Take a break, drink some water to replace your fluids and to help stave off any hangover. Now get ready for step two.

Here's the only weenie part I found about the design of this. Find the 1"x 1"x 12" bar that came with the kit. If you haven't prepared for this step, don't sweat it, you can do this later. Just bolt it on for now using the two longest bolts still in the parts kit. It goes on the tailgate using the top holes of the spare tire bracket. The plans call for you to use a non-existent rubber bumper screwed into a non-existent hole in the center of this bar. Danny later told me I was supposed to cut one of the original rubber spare tire bumpers from the tailgate. If you look at that like I did I'm sure you'll agree...weenie set-up.

Instead, I headed over to the local RV place and picked up a few things: 2 rubber door bumpers. The parts lady told me they were pretty much universal. Anyhow, they are about 2" diameter at their widest point and about 2" tall. If you got the license/brake light/license plate light kit, you may want to pick up a square, four wire trailer light plug as well. Then hit the hardware store for two 8.125x50 metric bolts with matching flat washers. Those will replace the two long bolts holding the metal bar to your tailgate. [IMG][/IMG] [IMG][/IMG] Trim off the final 1/2" of the open end of the bumpers, drill the center of the bumpers and squeeze in the washers. Push the bolts through and bolt the bar onto the tailgate.

Now get ready for some more lifting. The plans call for three, but I recommend two of the very large washers and place them over the very large bolt sticking up from the top right of the bumper. Then take one of the fatter collars and place it on the shaft. Now find the latch and handle assembly. The handle needs to be attached to the latch. There are about six different combinations, but the one you want should look like this. You'll be using two allen wrench bolts and fitting lock nuts. Then slide the handle into the slot of the spare tire carrier rack with the latch assembly on the outside matching up with the three holes. The plans do offer a neat trick for this next step. Take a bit of masking tape and place it over the box end of the wrench. Use that to hold the nut in place while you start the bolt from the outside. [IMG][/IMG] Get those three bolts tight, turn the carrier over and CAREFULLY place it on the huge bolt sticking out of the bumper. Be very careful of the seal on the top. Take the time to straighten it out before you place the other collar and put it on the bolt so that it seats into that seal. Place the remaining four washers over the bolt then take that big honkin' aluminum nut and snug it down on top of those washers. I was lucky enough to have a 1 7/8 socket to do that with. Don't over tighten it. Just snug it down enough to take the play out of it.

If you look on the left side of the bumper, you will see a threaded hole on the small vertical part of the bumper above the rubber pad. Take the round rubber bumper, matching bolt, washer and black metal sleeve (about 1" long.) Bolt the rubber bumper into that hole so the rubber is touching the rubber pad already bolted to the bumper. [IMG][/IMG] Tighten the striker. Pull up on the positive stop that is attached to the pivot on the tire carrier and swing it closed. Make sure the carrier is all the way latched. If it won't latch at all, take the carrier off and remove a washer. Then make sure the carrier rides on that rubber pad. If it doesn't remove yet another washer. Adjust the carrier up or down until it is about 1/16-1/8" below that rubber pad right before it is closed.

Screw the grease fitting into the small hole on the pivot and fill it with grease. The manufacturer recommends you remove the fitting once grease starts to ooze out to release any pressure. Then, of course, reinstall it.

Take one of the lug bolts from the kit, tap it in through one of the top holes in the round part of the tire carrier. Pug a lug nut on it and cinch it in. Don't get all Hurcules and break it off. If you tap on the head while tightening it, it will go in fairly easy.

Place the spare on and put in the two remaining lug nuts. Tighten as much as possible, remove the spare and finish setting them. Replace the spare and test the carrier for play and correct height. Then take those original spare tire bumpers and put them back from where you got'em. That will plug some holes and just as important, it'll save your tailgate from scratches when you have the gate open.

Adjust if necessary and you're done! Unfortunately, I'm only allowed to post 15 pictures for this write up there are over 20 more in my gallery at http://my.project-jk.com/showgallery...e=1&ppuser=635

 

Great write up!

David

 

wow, thats quite a write-up. you should send that to the vendor as an instruction manual. good job!

 

Thanks,
It was even better with all the pictures.

 

Excellent timing... just ordered my Rock Hard from David!

 

" Excellent timing... just ordered my Rock Hard from David!"

Hard to beat the free shipping on something like this. If you run into any problems don't hesitate to write. Let me know if you got the extras. They don't come with any instructions. I can definitely give you a few pointers there. I'm planning another write up for that stuff

 

That is a great write up. I have had this rear bumper on my JK since they were available and have been very pleased with it. So pleased in fact that I just ordered his front bumper too. The Manual was sparse but everything was straight forward on the install....Wipeout

 

We'll talk when we meet next week and you can show me exactly all the caveats! Look'n forward to it.

 

Hey Seer, thanks again for picking up those bump stops for me... they worked out great. I also put in my original 3rd brake light back in... turned out nice.

 

That is one sweet looking rig you have Donnie! I like that brake light set up you did. I'm still not all that excited about the spare tire license plate bracket on mine. That wiring seems too fragile for a 4x4. I may go to something like yours for a plan B.

I'll be writing you about those tires in a few days.

Nice job on the bumper!