Jump to content

Inverting (Flipping) Teraflex Falcon 3.1 Jeep JK Rear Shocks

Recommended Posts

Posted (edited)

the clearance problem:


i've been very happy with the quality and performance of the Falcon 3.1 shocks, however the rear ones really suck for clearance on a JK/JKU. Teraflex has some valid reasons for designing them to mount with the reservoir down. however, the OEM rear lower mounts already hang really low, so adding in the extra width of the reservoir turns those into total land anchors. for someone that rock crawls, the clearance problem outweighs any benefits.




this project started with some up-travel that wasn't being used due to my current bump-stop spacers. the bump-stops are pretty much dialed-in for my tire size, fender clearance, and other factors. i was going to switch from the Teraflex light-duty Falcon skids to their HD skids which can raise the lower shock mounting point by nearly an inch (or more depending on which set of holes you use).


however after putting on the HD skids, i still just couldn't stand how much clearance i was losing and decided that i needed to either flip the rear Falcons or ditch them for a different brand.


i called up Falcon/Teraflex who confirmed that even though they were designed to be mounted reservoir-down, the internals of the shock would in fact work perfectly fine inverted - but they definitely would NOT just bolt-in that direction without custom mods.





how to flip the rear Falcon shocks:


the first problem was the factory upper mounting bracket. i had to cut and bend a large "notch" to clear the reservoirs. 




then i didn't have to change the lower mounts for this flip, but i still wanted to raise them for even more clearance (not to mention i'd already butchered the OEM brackets during my first plan to use the Falcon HD brackets).




FYI, this 9" carbide tooth reciprocating saw blade worked much faster than a cutting wheel for hacking off the factory bracketry, then i was able to just do a little clean up with the grinder.


several companies make brackets to raise the lower mounting point - Synergy, JKS, Barnes, and Evo, just to name a few. i went with the Evo's RockStar Skid option mainly because they also move the mount outboard (closer to the tire), so you not only gain clearance underneath, but also reduce the width of the rear bracketry and potential boulder contact area.


the Evo brackets raise the mount about 1.5", which was going to be cutting it really close in terms of how much up-travel i had to spare - more on that later.




the next issue to solve in order to clear the inverted shocks was the rear sway-bar. you have to either remove it completely, or with an aftermarket exhaust and enough wheel backspacing, you can relocate it.


i first tried Synergy's relocation blocks that move the bar back and down, but my exhaust was in the way. however, i realized it would fit by moving it straight backwards just the width of its bushing bracket. i only needed to drill one new hole in the frame on each side and use a couple 3/8" thread-cutting bolts.




the new location for the sway-bar just clears above my Hooker Blackheart exhaust but leaves plenty of space for the inverted shock reservoir.




i had to also flip my Teraflex rear sway-bar links so that the articulating joint was at the bottom. otherwise the long mounting stud would contact the rear track-bar bracket on the passenger side. the bottom of the link also needed to be mounted inside the new Evo bracket in order to clear the brakes.




the top of the links still had to be mounted on the outside of the sway-bar leaving just enough room for them to not hit the tire or track-bar bracket. i think my wheels have about 4.5" of backspacing, which would then be the maximum allowable in order to relocate the sway-bar.


i did order some thinner lock-nuts to use in place of the one you see below, to get full thread engagement on the shorter 55mm bolt and provide a tiny bit more clearance between it and the track-bar mount.




a quick off-road flex test confirmed that my extended brake lines were still long enough, and that the new location for the sway-bar didn't put it at risk of inverting. the driver's side shock still comes very close my lower track-bar bracket with the new Evo mounts, but does clear it.




however, the zip tie test indicated the new Evo mounts are just a little too high - i.e. the shocks are able to bottom out. i was worried this might happen because the best i could tell with a measuring tape, the final available up-travel on the shocks looked to be about 3" but my potential up-travel at the bump-stops looked to be just slightly more. 




i could extend my bump-stops even a 1/4" and likely prevent the shocks from over-compressing. but 3" is already not much up-travel, so instead of reducing it further, i think i'm going to try and drill new mounting holes in the Evo brackets to lower them slightly.



before & after:


before (with the Falcon HD brackets raised to position #2):








the increased clearance under the new mounts is good, but the real payoff from the flip is a huge reduction in the width of junk hanging down below the axle.


and old photo looking backwards from under the rig (before the flip and still with the OEM lower mounts) :







Edited by theksmith
  • Like 4

Share this post

Link to post
Share on other sites

Great work K! 

  • Like 2

Share this post

Link to post
Share on other sites

Nice job Kris and great pictures.

  • Like 3

Share this post

Link to post
Share on other sites
10 hours ago, dzJeepChic said:

Great work K! 


thanks! just getting her in better shape to tackle the Dusy... now you better get those fingers crossed to get your axle in time ;)

  • Like 1
  • Love 1

Share this post

Link to post
Share on other sites

<pun> Nice flippin' work man! </pun>

  • Haha 3

Share this post

Link to post
Share on other sites
Posted (edited)

still working on finalizing this project...


i drilled new holes in the Evo shock relocation brackets so they could mount a little lower and also changed out my homegrown 4.5" bump stop extensions for new 4" ones.






i had to flip the upper trackbar bolt as it was hitting the new extension on the passenger side.




the new setup worked out just right as far as not bottoming out the shocks and i'm happy with the balance of clearance, up-travel, and droop.




i think my final issues are just with the sway-bar & links. the link on the driver's side now contacts the brake caliper on full droop. i also realized that i was wrong about whether the sway-bar was in danger of ever inverting - it could in fact flip over if the axle fully droops. i had only checked before with one side at a time down (under full articulation). 


i bought some JKS 2943 Rear Adjustable Swaybar End Links, but haven't installed them yet. i think adjusting them to just a bit longer than the current links will solve those issues and still clear the tire sidewall.


Edited by theksmith
  • Like 4

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...