Need Advice - I want to install Long Arm Kit

[Jerzey Girl]

My husband gave me the green light on the long arm suspension for my 2022 392. The Terraflex long arm kit comes IR or CT, I would like to save money and get the CT but the joints seem much better on the IR. I have looked for info on this forum but not too much about long arms. My 2020 JL Rubi has RK 3.5 mid arms with Fox 2.5 shocks, one of my goals with the long arm kit is to obtain a better ride, I feel the ride on the RK is rough. I would like to run 38" Nitto tires on Fuel wheels with 4.53 backspacing. Aftermarket fender flairs that are paintable. And Fox 3.0, but I might be able to only afford Fox 2.5, well see...
Fussion axles are Not in the budget at this time but I'm working on that issue. I was told the drive shafts would also need replacement in time because of tearing, no problem Adams drive shafts is in my town. I want to make sure after the money is spent, I don't wish I did something different. Advice is appreciated.

 

[ParadigmDawg]

After the fact, I wish I had of just spent the extra money and went with the long arm kit. It wasn't that much more. That being said, my Teraflex 3.5 RT3 kit rides great both on and off road. When I pulled the mechanic at my shop over to the side, to discuss what I should go with, the first thing he stated was "IR" over everything. Then he said the mid arm would be a lot better than stock and as long as I didn't drive a 392, with a long arm kit, then I would never know what I was missing and that's okay too. Spend it now vs wishing you had of. I feel like I will end up going long arm before it's all said and done.

 

[KTM300-152S]

FWIW
I too am on an EVO long arm kit 4.5" lift, with 38s, and the Fox 3.0s, + other mods

Changes/upgrades made completely changed the vehicle...

Stock XR had 2+" of up travel...maybe. No more riding the bump stops at +30mph...

But I live in the west where I have rocks and lots of open space and I'm really just an old dirt bike guy!!

 

[prodriquez]

I’ve covered this topic before so I’ll let you search my answers for the long explanation…

The short explanation is that you won’t find much on this topic because JL does not benefit from a long arm suspension in the same way that JK’s did. In fact, a JL will only benefit from a long arm suspension if you’re specific build is extremely tall, at ride height, and designed around maximizing your suspension up-travel. A desert racer is a good example

If this isn’t you… save your money and put it towards something because an adjustable mid-arm will handle up to a 40” tire and you won’t get hung up on them in the rocks

 

[KnoxRents]

I’ve covered this topic before so I’ll let you search my answers for the long explanation…

The short explanation is that you won’t find much on this topic because JL does not benefit from a long arm suspension in the same way that JK’s did. In fact, a JL will only benefit from a long arm suspension if you’re specific build is extremely tall, at ride height, and designed around maximizing your suspension up-travel. A desert racer is a good example

If this isn’t you… save your money and put it towards something because an adjustable mid-arm will handle up to a 40” tire and you won’t get hung up on them in the rocks

Yes. Unless you are lifting to the point of overly steep control arm angles, a long arm will do nothing for ride quality. Spend the money on shocks and springs in that order. The TJ and 2 door JK were very prone to steep control arm angles when lifted which would send the impact vertically up into the frame instead of laterally along the frame while allowing for the springs and shocks to do their job.

One geometry change that used to be very apparent on the JK was the brackets that AEV developed to to realign (lower) the front control arm pivot points to reduce nose squat when braking. AEV fixed Jeep engineering's geometry mistake in my opinion but with the proportioning valves weighing heavily to the rear brakes nowadays and better geometry, I have not heard complaints or felt any braking squat myself on JL.

 

[ParadigmDawg]

I’ve covered this topic before so I’ll let you search my answers for the long explanation…

The short explanation is that you won’t find much on this topic because JL does not benefit from a long arm suspension in the same way that JK’s did. In fact, a JL will only benefit from a long arm suspension if you’re specific build is extremely tall, at ride height, and designed around maximizing your suspension up-travel. A desert racer is a good example

If this isn’t you… save your money and put it towards something because an adjustable mid-arm will handle up to a 40” tire and you won’t get hung up on them in the rocksView attachment 34286

Very interesting. I will just be happy with what I have then, I mean, it works great.

 

[Earl 392]

I’ve covered this topic before so I’ll let you search my answers for the long explanation…

The short explanation is that you won’t find much on this topic because JL does not benefit from a long arm suspension in the same way that JK’s did. In fact, a JL will only benefit from a long arm suspension if you’re specific build is extremely tall, at ride height, and designed around maximizing your suspension up-travel. A desert racer is a good example

If this isn’t you… save your money and put it towards something because an adjustable mid-arm will handle up to a 40” tire and you won’t get hung up on them in the rocksView attachment 34286

Yep I see the long arm Jeeps in our group hitting rocks and dragging along those arms . Some times getting hung up on those arms too. Shorter arms seem to clear the rocks better just what I have observed while spotting

 

[Jerzey Girl]

After the fact, I wish I had of just spent the extra money and went with the long arm kit. It wasn't that much more. That being said, my Teraflex 3.5 RT3 kit rides great both on and off road. When I pulled the mechanic at my shop over to the side, to discuss what I should go with, the first thing he stated was "IR" over everything. Then he said the mid arm would be a lot better than stock and as long as I didn't drive a 392, with a long arm kit, then I would never know what I was missing and that's okay too. Spend it now vs wishing you had of. I feel like I will end up going long arm before it's all said and done.View attachment 34275

Thank You, that is helpful info. Nice looking 392!

 

[Jerzey Girl]

FWIW
I too am on an EVO long arm kit 4.5" lift, with 38s, and the Fox 3.0s, + other mods

Changes/upgrades made completely changed the vehicle...

Stock XR had 2+" of up travel...maybe. No more riding the bump stops at +30mph...

But I live in the west where I have rocks and lots of open space and I'm really just an old dirt bike guy!!

We live in the west also, counting the days till EJS had to miss it this year.

 

[Jerzey Girl]

I’ve covered this topic before so I’ll let you search my answers for the long explanation…

The short explanation is that you won’t find much on this topic because JL does not benefit from a long arm suspension in the same way that JK’s did. In fact, a JL will only benefit from a long arm suspension if you’re specific build is extremely tall, at ride height, and designed around maximizing your suspension up-travel. A desert racer is a good example

If this isn’t you… save your money and put it towards something because an adjustable mid-arm will handle up to a 40” tire and you won’t get hung up on them in the rocksView attachment 34286

I forgot to mention, I live in the desert and the Jeep will NEVER be seen at a mall or supermarket. I'm building this Jeep to be comfy offroad. Moab trails and desert. I feel the long arm will give me a better ride. The setup we have now is on a 2020 JL Rubi 3.5 RK Fox 2.0 shocks, it's much better ride than my JK. I don't like when we slam down on the bump stops.

 

[TRMFAM]

Hmm…great topic and asking for grace and help with my ignorance?

Why would a long arm ride better for Moab, street or crawling in general?

From a physics standpoint I understand that shorter arms have a more severe angle at the extreme ends of suspension articulation and are trying to push the axle away or pull it in but in that entire 60% range from dead center ride height to 30% up / down the angle should not be severe enough on a mid arm kit to ride differently? Please correct my thoughts here…

I fully agree if you are putting 16” coilovers on and running 102 mph across the dessert and spending a lot of time at the opposite ends of cycling that the arc reduction from a longer arm would pay dividends but I am struggling for most of our driving the differences. And I agree if you are running a 6” lift that 60% I referenced above as an example shrinks dramatically to only have maybe 30% to be in the “sweet spot” of the arms arc…Need someone that has done math in the last 30 years to calculate if above X ride height the CA will need to be longer to keep the axle travel happy translating to suspension working in the desired plane.

Ugh, my brain hurts!

 

[prodriquez]

Okay, I found my detailed post here
Post in thread 'Long arm vs Short arm'
https://www.jeep392.com/threads/long-arm-vs-short-arm.3048/post-50080

Here is what I said:
Long arms were a required upgrade if you wanted to lift any of the previous jeep generations (JK and older). They corrected the suspension geometry so lifted Jeep owners could regain their on-road ride quality and add some off road articulation.

Jeep corrected this issue with the current (JL) generation (in part) by moving to a mid-arm configuration. This was a huge change because it created enough room to correct the suspension geometry, via aftermarket adjustable control arms, after being lifted.

For the JL to benefit from a long arm suspension… I look at any build that is going to ride really high (~6+ inches) so they can maximize the up-travel in their suspension and maintain a relatively horizontal control arm geometry. This would include the desert racers and anyone going high speed over some big jumps.

In contrast, rock crawlers and mall crawlers want a low center of gravity so they don’t roll over going around a corner or coming off a rock. For these builds, a good mid-arm kit can easily accommodate up to a 40” tire.

Specific to the rock crawler crowd, I know 2 guys that went to long arms. The first guy has more money than brains, has to run limiting straps because his shock travel wasn’t sized for his suspension, and he has over 20k instagram followers! The second guy removed his long arms because he kept getting hung up on them in the rocks.

In summary, they look cool, they aren’t cheap, I think they ride the same, and you can absolutely expect to drag them over large rocks and obstacles.

 

[prodriquez]

@TRMFAM
There was a huge difference on JK and earlier jeeps because they came with short-arm suspensions. This meant that even the smallest of lifts would dramatically change their driving characteristics because your OEM control arms went vertical. This resulted in bump-steer, poor handling, and a rougher ride.

To correct this, people would install a long-arm suspension, on their JK’s, which simply involved pushing the control arms further out to correct the steering geometry. JL’s do not have this issue because Jeep completely reengineered everything and made it much easier to lift our vehicles without having to weld on parts!

For the JL, a long arm does NOT improve on road handling because the mid-arms are more than sufficient to bring your steering geometry back to speck. Sure, a long arm will mount ~6” to 8” further back… but they will only gain you maybe 2-degrees on an already level control arm, which is insignificant.

In the rocks, however, long arms do not allow for more articulation because your shocks and your springs are the limiting factors on a JL. Heck, I’m on 40’s, 1-tons, and I run 14 1/2” coilovers and I still wouldn’t benefit from a long arm suspension . Plus, long arms are much more prone to failure because they extend beyond your wheels and get hung up on obstacles as you crawl over them.

As with anything, it’s all about what you want to do with your Jeep(s), how much you want to spend, and what trade offs you need to make to get there. A desert runner can rock crawl and a rock crawler will perform reasonably well as a desert runner. Neither will be great at both.

 

[Jerzey Girl]

@TRMFAM
There was a huge difference on JK and earlier jeeps because they came with short-arm suspensions. This meant that even the smallest of lifts would dramatically change their driving characteristics because your OEM control arms went vertical. This resulted in bump-steer, poor handling, and a rougher ride.

To correct this, people would install a long-arm suspension, on their JK’s, which simply involved pushing the control arms further out to correct the steering geometry. JL’s do not have this issue because Jeep completely reengineered everything and made it much easier to lift our vehicles without having to weld on parts!

For the JL, a long arm does NOT improve on road handling because the mid-arms are more than sufficient to bring your steering geometry back to speck. Sure, a long arm will mount ~6” to 8” further back… but they will only gain you maybe 2-degrees on an already level control arm, which is insignificant.

In the rocks, however, long arms do not allow for more articulation because your shocks and your springs are the limiting factors on a JL. Heck, I’m on 40’s, 1-tons, and I run 14 1/2” coilovers and I still wouldn’t benefit from a long arm suspension . Plus, long arms are much more prone to failure because they extend beyond your wheels and get hung up on obstacles as you crawl over them.

As with anything, it’s all about what you want to do with your Jeep(s), how much you want to spend, and what trade offs you need to make to get there. A desert runner can rock crawl and a rock crawler will perform reasonably well as a desert runner. Neither will be great at both.

This has been very helpful and makes sense. I have called several of the suspension companies before making this post, the lady at Terraflex was like your lift is about arms and springs pick them out and install, called back to talk about the CT vs IR guy was like it's the joints, yes I know that but he could not elaborate on the topic.

 

[Jerzey Girl]

@TRMFAM
There was a huge difference on JK and earlier jeeps because they came with short-arm suspensions. This meant that even the smallest of lifts would dramatically change their driving characteristics because your OEM control arms went vertical. This resulted in bump-steer, poor handling, and a rougher ride.

To correct this, people would install a long-arm suspension, on their JK’s, which simply involved pushing the control arms further out to correct the steering geometry. JL’s do not have this issue because Jeep completely reengineered everything and made it much easier to lift our vehicles without having to weld on parts!

For the JL, a long arm does NOT improve on road handling because the mid-arms are more than sufficient to bring your steering geometry back to speck. Sure, a long arm will mount ~6” to 8” further back… but they will only gain you maybe 2-degrees on an already level control arm, which is insignificant.

In the rocks, however, long arms do not allow for more articulation because your shocks and your springs are the limiting factors on a JL. Heck, I’m on 40’s, 1-tons, and I run 14 1/2” coilovers and I still wouldn’t benefit from a long arm suspension . Plus, long arms are much more prone to failure because they extend beyond your wheels and get hung up on obstacles as you crawl over them.

As with anything, it’s all about what you want to do with your Jeep(s), how much you want to spend, and what trade offs you need to make to get there. A desert runner can rock crawl and a rock crawler will perform reasonably well as a desert runner. Neither will be great at

Hmm…great topic and asking for grace and help with my ignorance?

Why would a long arm ride better for Moab, street or crawling in general?

From a physics standpoint I understand that shorter arms have a more severe angle at the extreme ends of suspension articulation and are trying to push the axle away or pull it in but in that entire 60% range from dead center ride height to 30% up / down the angle should not be severe enough on a mid arm kit to ride differently? Please correct my thoughts here…

I fully agree if you are putting 16” coilovers on and running 102 mph across the dessert and spending a lot of time at the opposite ends of cycling that the arc reduction from a longer arm would pay dividends but I am struggling for most of our driving the differences. And I agree if you are running a 6” lift that 60% I referenced above as an example shrinks dramatically to only have maybe 30% to be in the “sweet spot” of the arms arc…Need someone that has done math in the last 30 years to calculate if above X ride height the CA will need to be longer to keep the axle travel happy translating to suspension working in the desired plane.

Ugh, my brain hurts!

 

[Jerzey Girl]

Hmm…great topic and asking for grace and help with my ignorance?

Why would a long arm ride better for Moab, street or crawling in general?

From a physics standpoint I understand that shorter arms have a more severe angle at the extreme ends of suspension articulation and are trying to push the axle away or pull it in but in that entire 60% range from dead center ride height to 30% up / down the angle should not be severe enough on a mid arm kit to ride differently? Please correct my thoughts here…

I fully agree if you are putting 16” coilovers on and running 102 mph across the dessert and spending a lot of time at the opposite ends of cycling that the arc reduction from a longer arm would pay dividends but I am struggling for most of our driving the differences. And I agree if you are running a 6” lift that 60% I referenced above as an example shrinks dramatically to only have maybe 30% to be in the “sweet spot” of the arms arc…Need someone that has done math in the last 30 years to calculate if above X ride height the CA will need to be longer to keep the axle travel happy translating to suspension working in the desired plane.

Ugh, my brain hurts!

 

[TRMFAM]

I am not a hater…you asked for opinions and you received them from theory to practical experience to anecdotal.

The end state of my build is ORIs and long travel arms but I dont expect the day to day to see an improvement in ride but would be overjoyed to report it happened!

You might consider EVO, RPM, etc. long arm kits that move the links up higher then stock design under the frame but would definitely further necessitate the long arms because of less upper / lower separation.

My next iteration is axles, ordered last week, and leaning toward the SDI e-click live valves along with lots of trial and error with coil spring lengths to get clearance with the lowest height possible.

Good luck on your journey and please share your experiences!

 

[Jerzey Girl]

I am not a hater…you asked for opinions and you received them from theory to practical experience to anecdotal.

The end state of my build is ORIs and long travel arms but I dont expect the day to day to see an improvement in ride but would be overjoyed to report it happened!

You might consider EVO, RPM, etc. long arm kits that move the links up higher then stock design under the frame but would definitely further necessitate the long arms because of less upper / lower separation.

My next iteration is axles, ordered last week, and leaning toward the SDI e-click live valves along with lots of trial and error with coil spring lengths to get clearance with the lowest height possible.

Good luck on your journey and please share your experiences!

any thoughts on WFO - they have a ton of videos on Youtube with long arm installs. Your information is very helpful and appreciated.

 

[paparex]

I went with Metalcloak long arm kit lock-load 3.5 lift on Fox 2.5 shocks with 37". No complaints
shipping the jeep in July to do the Rubicon Jeepers Jamboree. Anyone going want to do some wheeling after would be great

 

[Tank2112]

Thank You, that is helpful info. Nice looking 392!

I'd suggest you seriously consider what they are telling you about a long-arm lit for your JL. If you are not a serious rock crawler out wheeling every weekend, running long travel coil-over shocks, like 14" or longer...you'll see no improvement by going to a long-arm suspension. If you are that type of wheeler, don't forget the fully welded roll cage and a 5-point safety harness.
If you ask a suspension company's sales person, they may come up with a sale pitch as to benefits.... but it's just that, a sale pitch.
Long arms, by design, will drag on rocks.
38" tires on a mid-arm suspension is as good as you are going to get with your Wrangler 392 and still drive nice on-road.
There is also no advantage to using shorter travel coil-over shocks vs standard coil springs. Fact, standard coil springs will be more stable on-road and will still flex off-road to accommodate your 38" tires. Sometimes folks don't know what they don't know, and I'd hate to see you ruin the ride quality and stability of your 392.
I had a custom LJ for almost 20 years, with Hemi 6.1, Atlas 4-spd, Dynatrac ProRock 60's, Genright long-arm 14" coil-over system, 42" sticky Treps., etc.... Great rock crawler, not so good on hwy.
I will not do that to my 392XR.