Jeep JK OME BP51 Shock Install
So we made another major change. A change that wasn’t planned, at the moment at least, and didn’t come cheap. We recently decided to purchase a full set of Old Man Emu’s (OME) BP51 shocks.
A full set of OME BP51’s for the Jeep JK
We had always hoped to upgrade our shocks, but it wasn’t high up the priority list at the moment. However, this changed when we recently failed a state inspection because one of our rear Teraflex shocks was leaking. If we were going to be buying shocks again, we weren’t going to spend more money on something that we didn’t want. The Teraflex shocks weren’t that old either, as they had come with the lift kit that we had put on just as COVID was kicking off just over two years ago. At that time we had just bought a set of 35’s wanted and went with the Teraflex base lift kit as it gave us the clearance we needed and all research seemed to state that it was a quality product. We could have gone with higher-end shocks but couldn’t justify the money with the uncertainty around COVID at that time. Overall the lift has served us well, even though a large portion of it currently isn’t on the Jeep. Since then we have replaced the springs with AEV High Capacity Springs and changed out the Teraflex front sway bar extensions with a Curry AntiRock. All that is left are the extended brake lines, bump stop extensions, and rear sway bar extensions. We would have expected the Teraflex shocks to last at least a little longer.
The leaky Teraflex shock on top, BP51 on the bottom
If you had asked me a few months ago which shocks we would have gone with I would have most likely told you King remote reservoirs. But something kept pulling me back to the ARB Old Man Emu BP51s. Scott Brady from Overland Journal makes a strong case for them. They are vehicle specific, build to fit the specific stock vehicle requirements, and are not generic cross vehicle shocks like many of the options currently on the market. They are built and tuned from the factory for overland style travel rather than racing, and they are the only adjustable shock currently on the market that offers both adjustable compression and rebound which allows you to fully customize them easily to fit the specific characteristics of your vehicle and requirements for your next trip. The shocks can be adjusted in seconds with the supplied adjustment tool.
BP51s have adjustment collars for compression and rebound, the only product on the market that currently offers them
From the ARB site: “Adjusting the compression valving has an effect on how comfortable or firm the suspension is when the suspension of the vehicle compresses. Too firm and the vehicle will feel every bump and ripple in the road surface as the shock tries to prevent the spring from freely compressing. Too soft and the ride will become more comfortable, however, more body roll can be felt when tackling corners and the vehicle may nose dive during braking, resulting in less control. The suspension may also easily bottom out on the bump stops.
Adjusting rebound valving affects the rate at which the shock allows the spring to return back to ride height once it has been compressed. Higher rate springs are used to maintain correct ride height when either accessories or greater constant loads are added to the vehicle. When these springs are compressed with a greater load, the energy stored within the spring is also greater and requires extra damping control as it rebounds. Not enough rebound control may cause the shock absorber to top out, causing internal damage to the shock or allow the suspension to bounce numerous times after hitting an obstacle, resulting in less control of the vehicle.”
Adjusting the BP51s is simple with the supplied adjustment tool
The BP51s also have a unique bypass technology. According to ARB, “In addition to the velocity-sensitive damping used in most shock absorbers, where the faster the piston moves, the higher the level of damping is generated, BP-51 shock absorbers also generate damping dependent on the position of the piston within the shock absorber’s body via their bypass design. While most shock absorbers only generate damping based on fluid flowing through the piston, the BP-51 offers an alternative path from one chamber to the other, around the piston in the form of bypass passages. Some fluid flows through the piston and some fluid bypasses around the piston in the bypass passages. This results in an ability for the shock absorber to provide the best of both worlds, with a comfortable and compliant ride during normal driving and a more controlled ride over more challenging terrain. With greater levels of damping generated at each end of the stroke, the piston slows as it approaches full compression and extension, preventing harsh topping out against the bump stop and allowing larger bumps and corrugations to be absorbed more easily.”
We are overlanders and are more likely to see some time in the rocks than with high-speed driving, so a standard racing shock doesn’t fit our needs as well. ARB is well known for making some of the highest quality products for overlanders.
We are looking forward to trying these out on the trails, but everything has not started smoothly. We installed the rears a couple of weeks ago and they were a bear to install. At least for the Jeep JK, you will need to buy a fit kit for the front and back, these help to install the shocks and mount the reservoirs. Since these are vehicle specific I am not sure you need to buy a fit kit, shouldn’t it be included since they are vehicle specific? My rear fit kit seemed to be pre-opened. The bolts were loose in the bag, and there weren’t instructions or an adjustment tool included. I don’t believe that this was an ARB problem and was most likely caused by the retailer. Just as frustrating I called the retailer and they tried to tell me that ARB suspension products don’t come with installation instructions, even though the front fit kit did and there is a bright pick tag on the reservoir hose instructing you to check the provided instructions to ensure you install the reservoirs properly.
While not normally a big deal, the installation isn’t exactly straightforward even though it is literally only three bolts on each side. But there is an adapter that took a little while to figure out where it fits, and the shocks are difficult to position so that the reservoir doesn’t hit the rear sway bar.
The BP51 mystery spacer in question
It is a challenge to get the top of the rear shock installed. The stock shock configuration has two bolts that screw up into the body of the Jeep from below. But the stock shocks are slotted at the top, so you can start one of the bolts and then slide the shock onto the bolt and tighten from there. The BP51s are not bolts, but rather are Allen heads, and the top of the shock has holes, not slots. The adaptor that I mentioned about sits on top of the shock in order to give the top of the shock more room from the tub of the Jeep. So you need to hold the shock up, while balancing the adaptor on top, thread an Allen bolt through and try and line it all up. It is just as hard as it sounds. Once you get the bolts started it then takes you a while to tighten the bolts as you can only turn your Allen wrench barely a quarter of a turn before having to adjust your wrench, fun times. I am also concerned about your ability to tighten an Allen head sufficiently with only an Allen wrench in order to properly secure the shock. I am going to try and find the proper size Allen head for either my ratchet or impact gun to finish them off.
This is how the spacer fits on top of the BP51 to give it enough room to fit. When installed the bolt will need to face up from the bottom, which makes installation quite a pain.
I installed them and took them for a quick test drive. The rear shocks come from the factory with the rebound set to the middle setting and compression set to the lowest. After a short drive, it was clear that compression was way too soft and the Jeep was swaying like a boat on heavy seas. After several adjustments, I settled on the firmest settings for most road situations. Our Jeep is a heavy girl. The next day I took the Jeep an hour to pick up my wife from work. When I got out to move something to the back seat I saw that I was leaving a trail of fluid behind me. I looked under the Jeep and the rear right shock was just covered in oil and it was just pouring off. A few days later I finally was able to get the shock removed and the hose fitting on the shock body was completely detached.
Needless to say, this was a little disconcerting. I thought I was buying the best, as we often travel remote solo and we need our gear to work no matter what. And these shocks are not cheap, and it is more than a little frustrating to remove something that took several hours to install.
Why yes that hose is supposed to be attached
The benefit of purchasing from a leading brand is that they stand behind their product. I filled in the warranty form on their website that night, and by the next day, they had a new one out the door for me. I was very impressed and satisfied with the service. Hopefully, it was just a freak abnormality, and the next shock functions as it should.
I received the new rear shock about a week ago and was able to get it installed with less fanfare this time around. Fingers crossed that we don’t have another failure.
I installed the front shocks shortly before we left for our grand adventure. The fronts went on a little more smoothly. They were mostly complicated by the fact that I had several additional front-end projects that I got done all at once. Along with the front BP-51` shocks, I also installed the Metalcloak front Duraspring Bumpstops, front EBC Slotted Rotors, and Orange Stuff Break Pads, and AEV front Alignment Correction Brackets. It was a big job overall but went together rather smoothly.
OME BP-51 Front Shock for the Jeep JK
Similarly to the stock JK front shocks, the BP-51’s mount with the mounting shaft going through the top of the front shock mount and mounting with a bushing on each side and a locking nut on top. Having lived its entire life prior to our departure in Maine, my Jeep has a lot of rust. I have found it almost impossible to remove the nuts from on top of the shock. So every time I need to remove them I have used a saws-all between the top bushing and the shock mount to cut the mounting shaft and they drop right out. Thankfully I have not needed to remove the top bolt when I was not replacing the shocks. Whenever I need to extend the axle I just remove the lower mounting bolt.
Front mounting brackets for the bottom of the BP-51 Shocks both allow the fitment of the larger bottom shock head and pushes the shock outward to accommodate the larger shock body
Here are the mounting brackets installed. You can see where the stock shock mount location is on the left, and where the new location is pushed to on the right
After that, the mounting of the shock is relatively easy. To mount the bottoms you need to utilize the provided bottom mounting brackets that both allow you to fit the larger diameter shock end, as well as shift the location and angle of the shock outward to accommodate the larger shock body.
In the above picture you can see how the shock body is pushed outward allowing the fitment of the larger shock body
From there the last step is to mount the remote reservoir onto the frame in front of the spring. The brackets are a little awkward and take some finagling to get mounted and lined up, but overall are relatively easy. Just a note, due to the varying size of the frame rail, you will need to find the exact spot where the mount is supposed to go. You will know as it is the only place where the two parts of the mount will fit together perfectly.
The front reservoir mount has to be mounted in a specific spot in order to fit perfectly due to the varying size of the frame rail
Just like the rears, you are able to adjust both the compression and rebound of the shocks. After some testing of various settings, I Initially set the compression at 10, and the rebound at 7. I wasn’t happy with the performance though. The ride was comfortable, but I felt that the front end was too loose and displayed too much side-to-side sway after turns or sharp bumps. I set the rebound to 10 as well and have been happy with their performance ever since. Betty is a heavy girl, with a good deal of high-mounted weight with the roof rack and rooftop tent, which tends to make her a little tippy. So we ended up with settings of 10 for compression and rebound all around.
This is how the finished product looks once fully in place
After driving with them for over 6 months I would say that we are extremely happy with their performance. Onroad the shocks are firm enough to limit body roll at speed and allow for decent driving performance while also being soft enough to handle potholes, frost heaves, and speedbumps smoothly. While not overly extensive, we have tested the shocks offroad as well, including on some rather challenging trails in Uwharrie National Forest. Offroad the ride is similar. When combined with aired-down tires dare I say the ride is almost comfortable in even the roughest of terrains. Steep-off-camber situations also felt perfectly stable. At Overland Expo East on the driving course, the instructor had me drive high on the berm as he knew I had a capable vehicle and wanted to show me what the limits truly were. I would say that my nerve would have given way before the vehicle.
Most happily, we have not had a single issue or failure since our rear shock failed shortly after installation. We have been extremely happy with the shocks so far and have been very satisfied with the purchase. Other than basic shocks, we have not had the pleasure of using a lot of OME BP-51’s high-end competitors. So, this is not by any means a comparison, or statement that they are the best shocks out there. However, I will say that I would highly recommend them to anyone looking for a high-end replacement shock for a Jeep JK looking to combine both on-street performance with offroad capability and comfort.
