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Discussion Starter · #1 ·
This thread will show the evolution of my 2009 JKR. I have put a lot of hard work and thought into this JK. It is my favorite Jeep I have owned even though it is slow. I have made some mistakes and/or changes over the 12 years I have owned it. In no particular order I will try to document some of the things I have done along the way.


Oldest picture I can find, back in November 2009.
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First set of major mods; 35s, Bushwacker flat flares, Poison Spyder rocker guards and BFH front bumper, Rock Hard 4x4 rear bumper and tire carrier, and small lift in 2012.
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Finally on 37s with 2.5" lift, 2017
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37s on factory wheels with Tera44 housing, 3.5" lift and Metalcloak Overline flares and 6Pak shocks, Motobilt frame chop bumper, Smittybilt hinged tire carrier. 2019
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Finished with complete redesign of rear suspension with 1.5"-2" rear stretch and wheels with greater backspacing. April 2021
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The redesign of the rear suspension will be my first write-up and the biggest major mod I did that didn't come in a kit.
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Discussion Starter · #2 ·
After breaking the UCA mount on the rear axle because I was already playing around with the bracket, it was time to proceed with this project. We had fun on Holy Cross trail but broke going through French creek and decided that was a good time to turn around and call it a day. We drove home on a factory 3-link suspension.

I was initially working out the details. I cut and therefore weakened the UCA mount as I was fitting a bracket over the flimsy factory bracket. I was checking for clearance to decide on feasibility of this mod. It doesn't appear the upper mount will interfere with the frame rail during normal flex but I did recently remove the rear sway bar and increased the articulation in the rear. Removing the rear sway bar gave me a lot more articulation which caused 2 problems; Driveshaft now contacting gas tank skid plate, and need to find better mounting position of 13" 6Pak shock. Consequently, I lowered the rear upper shock mounts another 1".

Before the break, I wanted to make sure the height of the new UCA bracket wouldn't hit the frame rail.
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This is after the break, We drove it gently like this for a few weeks.
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My partner had a lot of fun driving most of Holy Cross trail picking her own lines.
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Discussion Starter · #3 · (Edited)
This project took me 10x longer than I had expected.

Things I learned and accomplished:
1. A relatively short arm 5-link suspension is difficult to to design/build that doesn't create link bind.
....A) Don't just articulate axle in a linear fashion when testing mounting locations, this won't necessarily show binding caused when fully articulating an axle on only 1 side.
....B) This suspension linkage was built around MetalCloak bushings which are forgiving; My suspension may not work with unforgiving heim joints and hasn't been tested with heim joints.

2. I honestly don't know my anti-squat and suspension numbers before (lifted stock) or after (newly relocated brackets) I did play with 4-link calculator but my knowledge is weak.

3. It feels good and I doubt that I made it worse than before; although, enough time passed that I can't say I remember how it felt beforehand.
....A) I'm sure a professional or someone more experienced could have done a better job than me.

4. I improved rear roll steer and increased my rear articulation. I need to find a better driveshaft (Probably 1410) due to the extreme operating angles of a 2 Door.
....A) A 4 door may not have the same driveshaft issue that I'm experiencing.
....B) I need a center limit strap to protect driveshaft while still allowing full articulation at the tires.

5. This may not work as well with a 35" tires but I suspect there would still be enough room for articulation except in the most extreme situations.

6. With my increased articulation, I am sure I will accelerate the wear of my MetalCloak joints and any other brand of quality rebuildable joints. I accept that as a compromise to my preference of a smooth and quiet ride. I have no desire to go to heim joints.

7. I have now created a problem where I can unseat my coil springs front and rear based on the near optimal position of my 6Pak shocks.
....A) I have some ideas and been in discussion with others that I will pursue over the next decade of ownership. No coilovers for me! 😁

8. I have greatly improved ground clearance at the rear axle while only losing .75"-1" clearance at the frame LCA bracket.
....A) Based on my current axle brackets, I don't see how a typical long arm would allow for my uptravel without contacting body mounts or more significantly reducing my frame side ground clearance.
....B) At this time I have no interest in relocating my gas tank and going with a properly setup 4-link or 3-link.

9. I have enjoyed the learning experience and I would recommend others look into alternative solutions. But be honest with your intentions and make your decisions based on the characteristics that are most important to you and not others.
....A) I like a quiet and easily drivable Jeep. I prefer easy and predictable maintenance. I can substitute a crappy stock shock in a worst case scenario.
....B) This Jeep will not be on 40s and I'll probably never do an LS swap. The next tire size may progress to a true 37" tire but I still have at least 20K miles on this set of tires.
....C) I enjoy the characteristics of the MetalCloak springs matched with the 6pak shocks. I have my own charging kit and understand the required maintenance of this style shock.
........1. I didn't want to cut into to the body for a longer shock. I enjoy the packaging of the 6Pak shock.
........2. These shocks, for me, are better than typical shocks included with the majority of the kits. They don't compare to race shocks or custom tune/valved shocks.
........3. I enjoy a spirited drive on dirt roads and moderate trails but I have no interest in getting air. Sadly, 95% of my miles are on paved road.
....D) I don't trailer my Jeep and I doubt that I will ever be in the position where I will want to trailer it.

10. 6Pak shocks are great for me but they require alternate mounting locations even when following MetalCloak recommendations. If you aren't utilizing the 13"-15" of travel, there is more than likely a traditional shock that will work for you.

11. Long-arm kits will not necessarily get you more articulation than a properly set up regular-arm suspension. The long-arm may offer smoother ride or better suspension numbers if done correctly. Don't assume that a long-arm kit is the best solution for your intended use of the vehicle.

12. My welding is not the best but so far it seems functional.😬

13. I have enjoyed what I have learned and I will continue to improve my Jeep to the best of my skills and knowledge.

14. I am open to discussion both good and bad but may not always follow it. 😉


After breaking things, I started ordering parts in August 2020. I was going to combine parts from Teraflex, Artec, RuffStuff, and Barnes 4wd, and wide open designs. I still haven't added truss as that will go on when I finally install my Teraflex 8-lug full float kit and new 8 lug beadlock wheels. I hope that will happen late this year or before 2022 wheeling season.


I ended up using the Teraflex track bar bracket because it was one of the few that raised the track bar 6" like an early Metalcloak bracket. This combo has worked well and allows for maximum uptravel while still allowing for an exhaust pipe and a relocated Evap canister. I did have minor contact with the frame crossmember and axle track bar bracket in the most extreme articulation when I was at 2.5" lift. I used this time to rotate the new Teraflex bracket to a better location after rotating the axle for pinion angle. I also did grind a little on the upper frame crossmember to make sure I have room for error. The Teraflex UCA bracket is good quality and offers 2" of additional height over factory. But I wanted even more height so I went with a RuffStuff bracket that offers 3" over factory height and 2.65" bushing width instead of 2 5/16" bushing. The wider bushing was a spare MC bushing I had from the rear LCA. It swaps easily between the joint housings with a pair of snap-ring pliers.
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This bracket worked well but due to the extra width and height and not specific to rear UCA mount of a JK, it did require more work. I had to grind the back of the bracket to give room for the rubber bushing to fully articulate. This mod wouldn't have been necessary for heim joints and something that the Teraflex bracket took into consideration. It needed grinding on the base to make it fit the axle bearing retainer flange. I will eventually add the lower reinforcement bracket after some mods that will come with the Full-float kit and axle truss. I also had to come up with a counter-sunk M14x1.5 100mm bolt so that the bolt head didn't dig into the frame or hard brake line at the limit of articulation. I am happy I went with this bracket for me;but, it would be easier to use the Teraflex bracket at the cost of some axle clearance to maintain the proper amount of joint separation.
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This is the RuffStuff bracket installed and tested on trail. It is hard to see but the upper bolt is counter-sunk into the bracket with an additional washer.
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Showing what I needed to grind on the bracket to allow the rubber bushing to flex and my first discovery of link bind during articulation. This bind was due to me increasing the joint separation based on the idea that I wanted to minimize axle wrap. Reducing the extra joint separation at the axle gave me more ground clearance than originally planned. This is when I realized my project was going to take way longer than anticipated and be more involved.
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This is when I started to realize I needed to come up with a better UCA bolt solution.
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Experimenting with a spare bracket, this was the solution for the bolt. I ended up using countersunk bolts in track bar which I will show later in this thread.
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Discussion Starter · #4 ·
An additional note on the UCA bracket.

Based on the choice of bracket, rotated pinion angle, and minor rear stretch, the UCA length is now approximately 21" as compared to a factory length of 17 7/16" and sits at approximately 3 degrees. I was no longer able to use the Metalcloak upper control arm so I swapped to using the straight MetalCloak rear lower control arms. This works well for me and I just swapped the frame bushing as the upper mount requires a narrow bushing. I'm currently running 2.75" Backspacing based on the wheels and spacers. I hope to be able to get that down to the 3.25"-3.5" range when I change wheels.

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A good picture of the bracket trimming to allow the flex of the rubber bushing and the improved clearance of a countersunk bolt.
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Discussion Starter · #5 ·
So now onto the LCA brackets.

I discovered that I needed to maintain roughly 9" of joint separation at the axle with only a small margin of variance before I ran into link bind even with the rubber/flexible Metalcloak joints. This worked well because It was close to the 25% of tire diameter rule. It also positioned the axle side lower control arm mount below the axle centerline and almost flush with the bottom of the axle tube. I looked into a couple different axle mounts and decided on the RuffStuff angled brackets because they offered the closest spacing to the axle. This allowed me to get more length in the LCA without moving too far forward on the frame. I wish I could have been closer to the original factory frame mount but I didn't want to go shorter than a factory length LCA. It is possible this could have netted me better suspension geometry but only someone with more experience than me would be able to respond to that. I could tell that if I could have raised the frame side LCA mount the 4-link calculator was trending in a favorable direction to the best of my limited knowledge. I couldn't tell if improving rear squat numbers at the cost of shorter control arms was worth the trade off. I would enjoy having a conversation about this. I selected the current position based on being able to use a factory or near factory length front LCA in case of repairs. I feel that I got the bolt hole as close to the frame while still allowing full flex/articulation of the MC Duraflex joint. Again it is possible that a heim or smaller bodied joint may have allowed a little more room to move up the bolt hole. The final reason was that I was concerned with the control arm contacting the frame during full uptravel. Without knowing any better, I am happy with the LCA position. I also like the fact that at least the frame LCA mount is level with the gas tank skid. The current LCA measures 22 5/8" which is length of factory front LCA as compared to the orginal length of 19 3/4".

Summary of decision for bracket locations:
1. I am able to use relatively common adjustable aftermarket front and rear LCA in case of damage/failure.
2. Maintained close to 25% of tire diameter to axle joint separation.
3.LCA mounts are no lower than gas tank skid and almost level with bottom of axle tube.
4. I didn't seriously compromise frame bracket clearance.
5. Greatly increased bottom of axle clearance. Some of this gain would be lost if I wasn't using MC 6Pak shocks.
6. By reducing the angle of the control arms and increasing the length I was able to significantly improve the problem of rear roll steer. With some additional trimming, I no longer have contact with gas tank skid plate.
7. Unintentional gain of wheelbase to approximately 97" which I see as a minor improvement. I hope to eventually achieve a wheelbase close to 100" if I can do a small front stretch to my satisfaction.
8. Although not drastic it does seem to absorb bumps better and feels good on the street.
9. I haven't noticed any loss of off roading and it appears to climb obstacles similar to before. I have already noticed the improved ground clearance at the axle.


This is what I hope is enough space to allow full flex and compression of the MC Duraflex joint. So far it seems good.
Automotive tire Rim Automotive wheel system Gas Automotive exterior
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I chose to go with Barnes 4wd JK LCA mount with some trimming to fit in new location forward on frame.
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Some trimming of the brackets.
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Testing various locations.This was not the final location.
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The final LCA location.


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The LCA is 22 5/8" long and angled approximately 4 degrees
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Discussion Starter · #6 ·
Track bar, bump stop pad, and coil spring write up.

The track bar also required some consideration during this build. I really enjoyed the feel of the 6" raise track bar bracket and I wanted to retain that height even though it had slight contact with a frame crossmember and an earlier configuration of the exhaust. I like the Metalcloak track bar as it seems to clear everything during articulation while being one of the highest ones. In fact they later reduced the height of their bracket to a more common 5" height. I chose the Teraflex track bar bracket as it is beefy and one of the few that offers 6" raised height while also being a stand alone complete bracket. I did trim the track bar bracket as I will eventually be installing the Artec Apex truss. There is still plenty of strength in this bracket and I probably didn't need to trim it this much but I will find out later. Originally MC used a countersunk bolt on the axle side of their track bar bracket to provide clearance to the 6Pak shocks. I decided to continue this trend even though I did relocate the shocks further back and rotated the bracket related to increased pinion angle. I have plenty of room on the driver's side but I believe I will try to improve on my shock position so I want to leave as much room as possible.

The frame side track bar area required some additional work as I was running into clearance between shock, Synergy track bar bracket brace, and factory located bump stop pad. The Synergy brace added thickness and a longer bolt in an area that didn't have a lot of room to start when you compressed the suspension on the passenger's side. It also did help that I now had a mini-stretch making matters worse. Moving the shocks back both at the axle location gave me the extra room that the shock needed in regards to the nut on the rear of the frame track bar bracket. I was still having problems with the bolt head on the front of the bracket contacting the axle tube/bump stop pad area. I carefully cut the top of the bump stop pads off and rotated them 180 degrees and shifted them as far forward as possible and this helped. The final step was to use the countersink bit to ream the track bar bracket and brace to allow a flush countersunk bolt. By doing these 3 things I got the room I needed without having to redo the factory track bar bracket on the frame. This also position the bump stops in a better location. Not necessarily related to the track bar but I also moved the springs forward using Artec Lower spring perches. A long time ago I had relocated and rewelded the factor spring pads to reduce the coil bend that is exaggerated on lifted 2 doors.

New position of spring pads and bump stop pads.
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Early position of shock clearance issue with frame track bar bracket.
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Getting closer to final solution.
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Ugly shock mounts but final solution with countersunk bolt
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It is blocked by the shock but at this point the axle track bar bracket contacted the crossmember. It was minor but I want to leave some wiggle room so I clearanced the crossmember.
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Crossmember clearance in case it is needed.
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Discussion Starter · #7 ·
MetalCloak 6Pak shock write-up.

I really like these shocks but they are not for everyone. They are a high quality rebuildable shock that have some very unique features that may or may not be useful for some people. I usually check and top off the Nitrogen charge once a year at the recommended 150psi.

Pros:
13" or 15" travel depending on shock.
Most compact shock based on stroke
4 shafts make it stronger than many "typical" shocks
Shaft speed is half a normal shock for same travel so should be resistant to fade compared to "typical" shock.
rebuild price is reasonable at $75 normal rebuild and $150 if damaged.
I have heard there can be some minor revalving done when sent for rebuild (haven't done it myself)
Can be used in other applications if you know what you are doing
Price is fair if you like the features and the way they feel.
Don't have to cut holes in frame or body to get long travel shocks.
Due to short collapsed length they have the potential to offer increased ground clearance compared to traditional shocks.
Even when damaged, they may still work in a limited capacity.

Cons:
Can be expensive if comparing traditional shocks.
Require annual check/recharge to 150psi of Nitrogen (some tuneable shock may require something similar)
Generally don't offer adjustments or valving choices. (???possible options when rebuilt???)
Most likely won't perform compared to similar priced custom valved/tuned shocks or racing shocks.
Application specific if following recommendations
Require rebuilding roughly 1-3 years depending on usage (this is similar to most high end tunable shocks).
Sensitive to orientation if custom mounting.
Are specifically meant to run with MetalCloak springs.
In JK application if bolting in stock position and not running overline flares and 35" tires you may not be maximizing potential travel.
Shock body is larger and may require more planning when installing.


If you do maximize the travel of these shocks, it can cause other issues;
Accelerated wear of suspension joints/bushings.
Need for better suspension geometry at the extremes of articulation (Increased roll steer)
Can cause additional clearance issues based on uptravel, droop, or cross articulation.
Increased chance of dropping or unseating a coil spring.
May need longer sway bar links, brake lines, sensor cables, hoses, etc.
May need different driveshafts


I originally designed the rear suspension around my 13" travel shocks but along the way I acquired a set of 15" travel shocks. The 15"s are currently installed while I have the 13"s boxed up to send in for a rebuild. The rears have taken a lot of abuse and I accidently blew a seal when I put them into a bind position while testing articulation The problem was corrected but the seal was already blown. The current position of the 15" travel shocks isn't optimal at the moment and could be improved just by adding spacers to the upper mount. I'm too lazy to optimize the 15" shocks as I just want to wheel and not kill my new driveshaft.

When I did the suspension work these shocks suited me well as I am able to run a 13" or 15" stroke rear shock (I have 2 sets) while not compromising ground clearance and not cutting holes in frame or body. I already had Synergy long travel upper shock mounts from when I had traditional style shocks. The addition of these brackets allowed me to run either 13" or 15" travel shocks without being more than 1" below the axle tube. I am sure that I could probably even increase the ground clearance by 1"-2" depending on chosen shock if I completely redesigned both upper and lower shock mounts not following factory constraints. My main problem at this moment is the limitation of my current 2 door 1350 driveshaft. My current driveshaft can't handle full droop from either shock. However, with a center mounted limited strap I could protect the driveshaft while still allowing independent articulation at the wheels. I haven't figured out how much droop/articulation I would gain by going with a 1410 or better driveshaft. I'm not sure if the juice is worth the squeeze.

It was difficult finding the best position during my mods but I also would have ran into similar issues if I had a traditional shock and was trying to maximize ground clearance. I feel I probably would have only been able to get away with a compact 10" travel shock if I wanted to maintain same current ground clearance. I will admit that it would have made some of this project a lot easier and I wouldn't have been so concerned with many aspects.

My lower mounts are ugly and I questioned the integrity of them long term, particularly if I drive fast on some forest roads. I also am trying to figure out a nice skid plate for extra protection. Luckily I haven't damaged them off road since they are already higher than stock but now I am trying harder stuff and I am increasing the risk of hitting them even in their higher location. The upper heim style mount and the combo of Synergy bracket gives me 2 different and easily adjustable mount locations. I can easily alter height of the upper location by using readily available spacers and bolts from Ace Hardware.

15" shocks installed and having fun wheeling.
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The upper position of the Synergy bracket provides about 2" of addition shock length based on the 6Pak mounting.
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13" shock almost full droop and brake line almost at its limit. Time for longer brake lines.
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Playing with union nuts and spacers to maximize articulation. May look shady but I have been doing various combo of these for the past 3 years with no problems..
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Discussion Starter · #8 ·
some random build pics and testing articulation in no particular order.

Early testing and failure when trying to maintain factory LCA mounts.
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Trying to figure out LCA mount
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What a mess!
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Early flex test
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Not bad, may trim more if I go to a true 37" tire
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No coil springs installed, Just enough room for Truss and Track bar if I can achieve this much full compression. More than likely I would reach coil bind or bump stop contact by then
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eBay is a good source for new or used bits
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Ugly but testing parking brake cable routing and function.
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Discussion Starter · #9 ·
Finally got out to play without any major issues.

Me and partner out having fun in mountain snow.
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She likes her new to her ShitBox. lol
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Both of us having fun flexing and taking pictures.
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Maxed out brake line
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Preview of the front
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Just enough room for driveshaft
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Back home, dirty and safe.


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Hard days work that inspired me to gut interior for cleaning and sound deadener.
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Discussion Starter · #11 ·
This was a great read for me on my lunch. Awesome looking rig and amazing work! A lot of it was far beyond me but it sure was entertaining and interesting.
Thanks for the compliment!
The only work I didn't do myself was gears and paint matching the the armor. I would guess I have 120 hours of work and research into this particular project. This was the 1st major suspension mod for me that didn't come as a kit or following someone's idea. I learned a lot along the way and made mistakes and fixed them; I look forward to doing similar stuff in the future.
 
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Discussion Starter · #12 ·
I still have a lot of stuff I want to add to this thread but I will post a quick successful project I just completed.

I have always hated how much the manual transmission shift lever wiggles around. It seems to have gotten worse as time has gone by. I decided to try just replacing the stock shifter handle while I wait to see if I can find a good deal on the B&M shifter assembly. I feel bad that I went with a Chinese knock-off but I couldn't justify the almost $200 for just the handle. This is what I found on Amazon for $95. It still has a rubber isolator and looks a lot like the B&M stick without the logo.. It didn't slide on the shifter assembly enough to tighten down the bolt so I ran emery cloth over the stub of the assembly and sprayed some silicone spray and it slid on easily and tightened down.

I like the end result, It feels great and doesn't wobble like the old worn stock handle. It has definitely delayed the urgency in wanting to get the B&M shifter assembly.

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Discussion Starter · #13 ·
I will add that after a few days I really like the new shifter handle. I had to learn the new shorter throws just from the reduced slop of the factory handle. It actually feels like I have a newer shifter assembly. I can't wait to eventually try the B&M shifter. It hasn't fixed the occasional pop out of 1st gear but I am more aware of when 1st gear is not properly engage and I can usually catch the problem before it pops out.
 

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Discussion Starter · #14 ·
I think it has been over 3 years since I installed the Teraflex heavy duty flipped steering linkage. I actually purchased it on Amazon as the standard non-flipped draglink link as it was on sale for $680. All I had to do was flip the cartridge style ball joint end o the draglink which I was able to do with a ball joint press. The joints were starting to flop and feel a little loose. I decided to watch the Teraflex video and adjust all 4 joints. They require 90 inch pounds for proper preload. I have a small torque wrench for my mountain bike that I used. 90 inch pounds is approximately 10 newton meters.

I also discovered on the 3rd joint that a T10 Torx bit works well after initial loosening using the specified 2.5mm allen key. Some of the spots are tight by the brake rotor. I used a small bit ratchet tool I got from sears a long time ago. I did the final tightening with the allen wrench as I didn't want to break the bit or strip the set screw. I'm going to find and purchase a 2.55 bit so I can use the small ratchet tool the next time I do this job. I removed 1 wheel as I was fixing a leak but it wasn't required for the other side. This is probably because I am running a combined 2.75" backspacing.

The joints feel new again and the steering linkage no longer flops around. There was no excessive play when I started and I consider the flopping to be normal once a new joint is broken in. I had no extra play or plunge of the joint that I could feel but it was clear that the original preload was gone.


I painted a yellow mark on the current position to see how much adjustment was needed to get the required preload.
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10nm almost got me to the next mark in the body of the steering ball joint.
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Additional tools I used.
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Nothing wrong with driving a GT (gutless turd) lol!

I recently started teaching my 15-yr. old son to drive in my 2011 Xterra. Pretty decent V6 motor with quite a bit of torque. Then I let my son drive the 2008 JK and his first comment was "it's too slow" and he prefers to drive the Xterra. That's fine by me, I didn't want to share the JK anyways!
 

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Discussion Starter · #16 ·
Nothing wrong with driving a GT (gutless turd) lol!

I recently started teaching my 15-yr. old son to drive in my 2011 Xterra. Pretty decent V6 motor with quite a bit of torque. Then I let my son drive the 2008 JK and his first comment was "it's too slow" and he prefers to drive the Xterra. That's fine by me, I didn't want to share the JK anyways!
yeah even though it is slow, I still have a lot of fun with it. I actually would like to see how it feels if I ever get it back to sea level. It has 5.13s, Ripp headers and tune, viper throttle body, and sometimes I install the K&N intake assembly.
 
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Discussion Starter · #17 ·
So tonight was not a good night. I thought I had figured out how to piece together the JK J8 brake booster and master cylinder kit that would work easily for manual transmission Jeeps.

I am still looking for the part number of the master cylinder that I installed a couple of years ago. I want to think it is a Crown automotive master cylinder that is larger than the factory 2009 master cylinder. I have had it for a couple years and it did improve the brake feel but I still had some sponginess. No matter how many times I manually bleed the brakes and proceeded to go on dirt roads and jam on the brakes to cycle the ABS I just couldn't get rid the the spongy pedal. I finally purchased a good power pressure bleeder and that made a big difference. It was finally time to add the J8 vacuum booster that I had been sitting on for 6 months. I was dreading the install since I would have to deal with the aluminum plate and the clutch slave cylinder.

After fighting to keep the aluminum plate in place and not cracking the lines on the brake system I was finally able to get out the stock booster. I didn't check close enough to realize the master cylinder bolt spacing and sealing area were different between the J8 booster and factory booster. I did figure out how to keep the aluminum plate in place. After loosening the engine side 4 bolts I was able to get a thin 1/4" drive 13mm socket through the interior body firewall holes and completely loosen the 4 flange bolts for the booster to aluminum plate. With the plate loose, I was able to wiggle the booster loose and the flange bolts dropped to the floor. With the flange bolts in hand, I went to Ace Hardware and purchased 8mmx1.25 nylock nuts with a slightly larger grade 8 1/4" washer. This was the largest diameter that would still fit through the firewall hole. This allowed me to loosely tighten the aluminum plate and attach the brake booster from the interior like all my previous Jeeps and Mustangs. The aluminum plate must be finger tight to allow it to wiggle a little to allow the 4 interior bolts, thin socket and hole to align. After the interior was tight, I finished tightening the exterior nuts for the aluminum plate.

Factory 2009 booster vs J8 booster
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Wrong J8 booster almost in place
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This is when I discovered the wrong bolt spacing
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Closer look at differences.
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Sealing face difference. I think J8 uses a square edge O-ring vs typical O-ring on factory unit
4521090


Diameter of Grade 8, 1/4" washer vs factory flange nut. This washer just barely fits through the firewall hole.
4521091


Plate in place and still able to install booster with different hardware. Future job should be easier.

Automotive tire Automotive exterior Tire Car Rim



These are the correct part numbers
4521093
 
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Discussion Starter · #18 ·
So I successfully returned the Jeep back to the factory default booster until I decide if it is worth the trouble to buy the complete kit and add the additional Willwood clutch reservoir. I'm holding off for now because the kit is on backorder and ordering the individual pieces is significantly more. I guess I should have been happy with the final improvement I made after using the Motive pressure brake bleeder.
 
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So I successfully returned the Jeep back to the factory default booster until I decide if it is worth the trouble to buy the complete kit and add the additional Willwood clutch reservoir. I'm holding off for now because the kit is on backorder and ordering the individual pieces is significantly more. I guess I should have been happy with the final improvement I made after using the Motive pressure brake bleeder.
Love this build thread!

A little forewarning... I attempted the J8 kit on my 17 (did a booboo and destroyed the MC, first job I've ever screwed up...) anyway I bought the popular Wilwood reservoir and the hose ID will barley allow for itself to be put on to the clutch MC. I was heating the hose in boiling water and trying to slide it over, trying to ream it out a bit with a drill and I'm telling ya it was a bear! I spent at least an hour and a half just trying to get the hose on that MC. Something to look into before you start. I'll be shopping for a new res kit when my next J8 kit finally arrives
 
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