Suspension comparison: AEV vs. Metalcloak vs. Teraflex

AEV DualSport XT (Photo courtesy AEV forums)

AEV DualSport XT (Photo courtesy AEV forums)

While I’m still a ways off from purchasing a full-featured lift kit for my Jeep, I thought it might be worthwhile to compare the features of each lift I’m considering. Let me say up front that each of these companies makes outstanding products, and I wouldn’t hesitate to do business with any of them.

The Jeep

Smokey is a 2009 two-door soft top Jeep JK Wrangler with the 3.8-liter V6 mated to an automatic transmission. As a daily driver, easily 99 percent of my driving is on the road, with the all-too-infrequent jaunt to the trail. A comfortable highway ride is very important, as my post-brain surgery wife and our two young kids join me in taking this Jeep on at least one long-distance trip each year.

Intended use

As a dual-purpose vehicle, Smokey needs to be capable of full-time, reliable use on the street, but be capable of moderate trail use. As my suspension is stock except for a set of Teraflex sway bar quick disconnects, I currently stick to mild or moderate trails. That said, there are a few more challenging obstacles in my area which I’d like to be better equipped to tackle.

I’ve defined my needs as a 2.5-inch lift (The three-inch Teraflex kit isn’t entirely out of the question.) and 35-inch tires. I’d prefer to avoid adjustable control arms, which means I’m looking at someone’s geometry correction brackets and a possible eventual upgrade to a set of longer-length fixed arms. I anticipate eventually moving to a set of flat fenders, as the idea of running 37-inch tires is tempting, even if I don’t currently wheel hard enough to need them. (Yes, I know other upgrades would be needed at that time.)

The contenders

I’ve been going back and forth between the 2.5-inch kits from American Expedition Vehicles and Teraflex for some time, knowing each caters to drastically different audiences. I’ve also tentatively added Metalcloak’s 2.5-inch “Sport” expedition lift.

Components & considerations

Coil springs: The heart of any Jeep JK suspension is the coil springs. Each of my three contenders addresses this point in a different way. All use identical types of springs fore and aft, as opposed to some manufacturers, which use variable-rate springs in the front and linear out back. AEV’s DualSport XT includes, as AEV describes them, “frequency-tuned, triple-rate coils at all four corners.” Metalcloak, too, utilizes a variable-rate coil, in this case a dual-rate coil that holds its lighter, “flex rate” coils in full compression at normal ride height. Building a more traditional configuration, the Teraflex kit includes four linear-rate springs not unlike those currently on the Jeep. Keep in mind, too, that both AEV and Metalcloak maintain the stock front-end rake; only Teraflex among these three is designed to bring the Jeep’s nose up to level.

Which spring is best for my use? My instincts say the progressive or dual-rate springs will afford the best ride on pavement. While the complexity of the AEV spring (a triple-rate spring plus transitional rates in between means there are, in fact, five rates for the shocks to deal with) could pose unpredictability, especially for my light two-door, the added free length of the Metalcloak dual-rate springs promises additional down-travel, so crucial in any modest lift. Advantage: Unknown

Fox 2.0 Performance shocks

Fox 2.0 Performance shocks

Shocks: As crucial to ride quality as the springs are what shocks are teamed with it. The proprietary tune in the AEV-sourced Bilstein 5100s promise to work seamlessly with their springs, while the Metalcloak lift doesn’t ship with shocks at all. That firm’s six-pack shocks are highly regarded, but are beyond my needs in terms of practical use and price. Teraflex’s lift is available with a rebranded twin-tube design but, were I to go the Teraflex (or Metalcloak) route, I’d bypass these for the stronger design and better cooling of either a set of standard Bilstein 5100s or Fox 2.0 performance shocks. Both of these are rumored to be too firm until sufficiently broken in, but after that, the ride is said to be supreme. Advantage: AEV

Bump stops: All three kits ship with adequate front and rear bump stops, though the Metalcloak stops are adjustable, allowing the user to dial in the length to whatever is appropriate to his or her application. The attachment method of the Metalcloak front stops does give me a little concern, though. With a large washer and button-head bolt repeatedly coming into contact with the factory upper stop, I can’t help but wonder if this won’t tear the OEM stop over time. Advantage: Metalcloak

Front track bar: A lift of this height will result in the front axle shifting approximately a quarter-inch to the driver’s side. Such a subtle shift doesn’t necessitate addressing the axle movement, but the issue is easily fixed with an adjustable track bar, which many manufacturers offer. Of the kits I’m considering, only the Metalcloak kit ships with the track bar. Advantage: Metalcloak

Rear track bar: All of these kits include a replacement track bar bracket to raise the Jeep’s roll center. The AEV bracket claims an increase of 4.5 inches. While I’ve been unable to locate specific measurements for the Teraflex and Metalcloak lifts, an image comparison suggests the Metalcloak bracket also significantly raises the track bar’s mounting point. The AEV kit also ships with an OEM-quality (in other words, mediocre) replacement rear track bar, which has been bent to clear the rear differential. The Teraflex and Metalcloak brackets mount on three planes, which some say negates the need to weld them in place. Advantage: Tie

Front sway bar links: New front links are unnecessary for my build, as I’m already quite happy with my Teraflex disconnects. If I didn’t have those, though, the AEV kit would require the use of mounting brackets to extend the factory locations. The Teraflex kit repurposes the Jeep’s factory rear links to the front, while the Metalcloak lift includes front and rear links. Advantage: Metalcloak

Brake lines: All three kits include a bracket to lower the rear brake lines to avoid overstretching. AEV also adds such a bracket for the front. Metalcloak includes longer replacement front lines which, while an annoyance to replace, offer a better solution than a simple bracket. Advantage: Metalcloak

AEV geometry correction brackets

AEV geometry correction brackets

Geometry correction: A lift of any height will change the factory caster and pinion angle. Returning these figures to near-factory settings can be accomplished with aftermarket control arms or with brackets that adjust the mounting point of the front arms. The Metalcloak lift comes with a set of brackets that, save for their welded structure, look like they could have come off an AEV assembly line. The brackets are a $105 option with the AEV kit, while the Teraflex kit does not include an option for geometry correction. Advantage: Metalcloak

Instructions: Any product is only as good as the instructions that tell the user how to install it. And, it is here that Metalcloak, which has done very well in this comparison so far, falls off the cliff. Metalcloak offers a single set of instructions for all its suspension kits, leaving it to the end user to weed through which parts apply to his or her purchase. AEV’s instructions are thorough and contain a lot of well-constructed diagrams. Teraflex includes thorough instructions with mediocre black-and-white photos, but the company’s online video collection is a tremendous help when installing their products. Advantage: Teraflex

Customer service: This one isn’t even a horse race. While there certainly are examples in the Jeeping community of outstanding service from AEV and Metalcloak, customer service is really where Teraflex leads the field. How many forums are filled with stories of parts being replaced, no questions asked? For that matter, how many other companies have such a large sales & support team crawling the interwebs, only too happy to offer advice to fellow Jeepers. In my view, customer service is the real “Teraflex Advantage,” and by itself is reason enough to choose this company’s products. Advantage: Teraflex

Looking over the comparison, now that it’s written, I have to say it appears much more one-sided than I expected. For me, the big question mark remains spring characteristics. I’ll continue to research these lifts and companies and, as I get closer to time to make a final decision, I’ll begin looking for more local Jeepers running these lifts to give me a hands-on examination.

As is the case with all the above components, Jeepers’ opinions are a very low-cost commodity, and enthusiast forums are filled with people swearing each of these options is the best, worst and everything in between. Many decry AEV as overpriced brackets for mall crawlers, even though TJ fans adored their springs before the advent of the JK. A glance under many race vehicles will prove Teraflex is a popular choice. But, is this for reasons of pure performance, or money well spent by what is arguably the industry’s best marketing team? I don’t have the answers. I’ve spent countless hours reading everything I could get my hands on regarding things like spring rate, roll center, instant center and more — enough to make my brain matter ooze from my ears, screaming for mercy.

So, with only a few more conclusions now than when I started, I invite your input, clarifications and/or sarcasm.


  1. So why did you go with Teraflex when your analysis favored Metalcloak or AEV? I’m trying to figure out what lift to put on my JK and I am finding out the more knowledge results in bigger migraines.

    Liked by 1 person

    1. I’ve actually not put on a proper coil spring lift yet. I needed to get tires, so I added a Teraflex leveling kit to make enough room. That 1.5-inch kit will come off when it’s time for another set of new tires, as my next tires will step up to 35s.

      I know what you mean — it’s often confusing, separating the important information from the marketing messages. Right now, I’m leaning toward the Metalcloak Overland Sport kit, to be followed later by a set of Teraflex fixed-length control arms.


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