ARB Rear Bumper installed (1 Viewer)

[MScruiser]

If anyone has Rock Warriors, and if you plan on using the center cap on your spare, you will need to cut about 2" off of the square stock in the middle of the spindle.

Also, you might as well throw away the 3 studs that came with the kit; they are the wrong size--12.5x1.50, when you actually need 14x1.50.. You will need to buy 3 new wheel studs from NAPA, and the NAPA part number is 641-4311.

And on that note, your new studs are too big to fit in the ARB spindle now, so you will have to drill out the existing holes with a 5/8" bit.

Then again, it's possible ARB just sent me the wrong studs, but due to the fact that the holes were also too small, I think not. Anyways, just check them before you install them, and be prepared for them not to fit.

 

[mooseknuckles]

If anyone has Rock Warriors, and if you plan on using the center cap on your spare, you will need to cut about 2" off of the square stock in the middle of the spindle.

Also, you might as well throw away the 3 studs that came with the kit; they are the wrong size--12.5x1.50, when you actually need 14x1.50.. You will need to buy 3 new wheel studs from NAPA, and the NAPA part number is 641-4311.

And on that note, your new studs are too big to fit in the ARB spindle now, so you will have to drill out the existing holes with a 5/8" bit.

Then again, it's possible ARB just sent me the wrong studs, but due to the fact that the holes were also too small, I think not. Anyways, just check them before you install them, and be prepared for them not to fit.

Nothing like trying to fit a square peg through a round hole.

If you cut off the 2" of stock, do you lose the rear holes to mount the Hi-Lift?

I picked up the 14x1.5 from Napa but have yet to have time to drill them out. Had to grab button head allen for the Hi-Lift mount due to the lack of clearance with the Rock Warriors. Currently carrying 2 lug nut keys. One for the 12's on the rear and one for the 14's.

 

[MScruiser]

You do lose the holes, but you could easily fab up a different mount and drill a new hole.

Just go ahead to drill those 3 holes out and ditch the 2 sets of nuts.

 

[highfructose]

Hey guys,

I've finished installing my rear bumper (minus the sensors). I have about 8hrs of work in it already, and maybe another 3 to go.

Here are some pics without the rear bumper, but after the quarter panels were cut:

ARB's instructions were wrong in a few regards, one of which was major.


1) The recovery loops that are below the vehicle are removed completely and are not reused. They use these as a main point the bumper is attached to. It would be nice if they simply provided longer bolts so these could be reattached.

2) I am not sure why ARB has the 6mm packers as separate pieces. Would it not have been simpler just to weld these onto the bar? It wasn't difficult at all to put them in place, but it just didn't make sense from an engineering standpoint not to just have these part of the bumper.

3) The bracket on the left side which holds some sort of electronic equipment at an angle is moved using the relocating bracket. When this is done, the O.E. bracket is lower and further forward. It interferes with the spare tire, if oversized from stock. I had to take a dremel and cut off some metal to allow this bracket to clear the tire.

4) There are two brackets in the center (to the left and to the right of the hitch) that need to be removed to clear the new bumper. They were used to support the plastic bumper. ARB makes no mention of these, but they need to be removed. They serve no purpose with the ARB bumper. This should have been in the instructions.

5) There is a piece of hollow tube steel which is welded attaching from one side of rear frame rail to the other near the hitch. This appears to be a cage for the spare tire. It simply supports the spare tire. There is a screw dead center where the spare tire wrench inserts to lower the spare. This bar must be removed as it interferes with the ARB bumper. I simply took a hack saw and cut this piece off. Again, I do not see this piece adding any structural integrity to the vehicle, especially once the ARB bumper is in place. However, ARB failed to mention anything about this piece. I will have to discuss this with ARB on Monday, but I cannot imagine that this piece is not on the AU models for which the instructions were written.

6) The gap on the left side between the cut bumper and the ARB is larger than on the right side. ARB states you MUST use the 6mm packers, but I question this. I may remove the packer on the left and see if I can get it closer. It's about 30mm on the left and 15mm on the right. If I remove the packer, I may be able to get it closer, but at the same time I don't want to to sit unlevel or raked. in appearance. We'll see what I do...

7) If the spare is in place while lifting the bumper on, even after those brackets and tube steel are cut, you will hit the rear of the spare tire. It makes it a lot easier to remove (or at least lower) the tire and then get the bumper on. Once in place, the tire when lifted will bind into the ARB bumper holding it securely in place. This is why that steel tube can be removed safely.


As a final note, I wanted to get the bumper on first before drilling the sensors as I wanted to know where the bumper touches (or comes close to) the rear frame rail and hitch. This way, I didn't make a large hole and regret it once the bumper was on. I'm going to find 4 locations that do not interfere and drill them with the bumper attached. It shouldn't be too difficult to wire it from behind, especially once the spare is removed and I have it on 6" risers.

I'm heading outside to do this now. It's a nice day as far as Tucson is concerned -- 96* is the high today. Last week was 108*!!!

Would anyone happen to know what the function of the “packers” are?

 

[Haggis]

I have the same bumper and love it. I certainly don't have the skills to do it myself and had a shop do mine. Super stout and looks great. I kept mine black but I like how you color matched yours!

 

[highfructose]

Would anyone happen to know what the function of the “packers” are?

To answer my own question: it appears that packers are basically a spacer that goes between the main chassis mounts of the bumper and the chassis/frame rail in order to ensure there isn’t a cant or tilt to the bumper.

Packers of various sizes appear to be included with the arb bumper because of loose manufacturing tolerances of the chassis/frame rail angles and the body bolted to it.

The packers may allow for an aesthetically and visually perfect “line” that the new arb bumper will follow…rather than the sometimes slightly off kilter aftermarket bumpers you see installed on vehicles.

Interestingly, even though arb provides packers in order to tilt a bumper 0-14mm, they do not provide longer bolts to mount the bumper at the oem tie down/recovery points should you determine you need 14mm of packers (plus since you use the oem bolts, they basically require you do not reinstall your factory tie down/recovery points-the thickness of the new bumper basically eats up that thread real estate on the oem tie down bolts).

…so you lose your oem tie downs/recovery points, take your oem tie down bolts, which have roughly 30mm of thread engagement, and, potentially, reduce the engagement by up to 14mm due to the use of packers…

I didn’t like the idea of losing factory or aftermarket recovery points so I purchased grade 10.9 M12 x 1.25 x 60mm so I can, hopefully, between the packers, bumper, and 14mm thick trail tailor recovery points, have the appropriate amount of thread engagement there (oem bolts, I think, we’re m12 x 1.25 x 40mm)

I think it’ll come down to how many packers I need as to whether these bolts work. I may be able to add a thick washer to the bottom in the event that I do not need too many packers.

Does anyone happen to know how many millimeters of thread “receiver” is in the frame rails that the oem tie down points bolt into?

 

[highfructose]

Everything in this thread was helpful. All the tips…all the cuts the op recommended were necessary.

I would add: the mudflaps are goofy. We ended up trimming them, heating them, drilling new holes, and bolting them on flush w the bumper. If you’re doing this job and want to speed up the mudflaps portion, buy the arb mudflaps.

The bracket relocation (#4 from arb instructions) was time consuming because the arb instructions aren’t super clear. The new bracket bolts in where the old one was…except pointed towards the front/drivers side of the vehicle rather than towards that back/rear bumper like it originally was. We trimmed most excess material from the oe bracket, bolted it to the new bracket also pointing towards the front/driver, and reversed the direction of the harness so it didn’t strain the wires. We also bent it slightly to ensure it would clear the spare. We took out several of the wiring loom clips to ease up the wire tension in this general area.

Without the spare tire bar that was cut out…or perhaps because of the bumper itself, the spare tire wobbled slightly. It was tight one front and back but not side to side. For now, a small piece of anti fatigue mat folded in half between the tire and the chassis acts as a washer to make it not wobble-there are little bump stops in this area to do what the foam mats are doing…they just need to be extended via washers or a puck. For now, the mats work great.

 

[Pierce]

I’m wondering (hoping) that this bumper does not interfere with a 12 gallon LRA aux tank. Has anyone here installed one of these rear bumpers that also has a 12 gal LRA Auxiliary tank as well?

I haven’t installed it yet. I’ve watched the video that @OTRAMM created about a half dozen times now. It appears that the spare tire support gets pretty close to the aux tank. Does the bumper intrude further than the spare tire hoop did?

Thank y’all for any info.

 

[highfructose]

I’m wondering (hoping) that this bumper does not interfere with a 12 gallon LRA aux tank. Has anyone here installed one of these rear bumpers that also has a 12 gal LRA Auxiliary tank as well?

I haven’t installed it yet. I’ve watched the video that @OTRAMM created about a half dozen times now. It appears that the spare tire support gets pretty close to the aux tank. Does the bumper intrude further than the spare tire hoop did?

Thank y’all for any info.

The second and third picture shows that the bumper sits about flush with the base of the bar that was removed…though the bow that curved towards the front of the car isn’t there anymore so I’d guess the arb bumper offers more clearance for tire/gas tank than did oem

32.9” tire in the photos.
I’ve got 0.25” between the bumper and the tire…and another inch between the tire and the sway bar

 

[Pierce]

@highfructose thank you for the pictures and information.

View attachment 3182214

View attachment 3182215

View attachment 3182216

View attachment 3182217
The second and third picture shows that the bumper sits about flush with the base of the bar that was removed…though the bow that curved towards the front of the car isn’t there anymore so I’d guess the arb bumper offers more clearance for tire/gas tank than did oem

32.9” tire in the photos.
I’ve got 0.25” between the bumper and the tire…and another inch between the tire and the sway bar