Years ago, and many miles ago, I purchased and installed a 2" spacer kit from AEV. I spoke directly to AEV about all concerns about this type of lift and they let me speak to one of the engineers who developed it. Their engineering staff includes a former Jeep engineer who helped to develop the JK suspension. They stated that there were no safety or wear/tear issues with this setup, and that it would perform fine off-road, even at full extension/compression.

After 42,500 miles, trips to Moab, Colorado, Windrock, and countless other off-road excursions in my local area, I can tell you that everything they told me about this kit was spot-on.

-It has been safe
-It has had no problems, whatsoever
-I'm running 33" BFG KM2's, and they have lots of tread life left in them. They are wearing evenly, and I see no unusual patterns, wich is exactly what I saw with the stock BFG KM's, which ran 60k miles.
-I've had the suspension maxed out MANY times with no issues, no popping, no tension noise, no difference than when it was stock.
-AEV boasted that the ride and handling would be very close to stock, which was exactly true. The handling on twisty roads is stable and comfortable, even when pushed hard.
-Suspension travel would be as good as stock. It extends enough that the wheels stop just short of rubbing, which is perfect.

I can't speak for other leveling or spacer kits, but the AEV works perfectly for me. One difference I noticed was that the AEV kit had extended sway bar links, which AEV told me were a critical piece for stability. After all the miles, I have to believe they were correct.

I'm still wondering what exactly the safety issue is that the shop was referring to. If they say there is a safety issue, and they still actually sell and install the kit, I think some attorneys would be interested in checking into that, as would the NHSTA. Surely, it says a lot about their character (read: lack thereof) if they even sell a leveling kit and openly admit there is a safety issue. They've really opened themselves up to all kinds of problems, not just in civil court, but with criminal charges, as well. If they installed one of these kits, and someone were killed in an accident where there was even suspicion the kit was to blame, they'd be looking at involuntary manslaughter or something very serious like that. Sounds like they are just unscrupulous and stupid.

I firmly believe that if there were a known and consistent safety issue, there would be recalls. My kit was registered with AEV, because I bought it directly from them. No recalls, so far. I've met others with this kit and they were as happy as me.

I actually thought I'd buy this kit at the time, and then later, when I had more money, would switch to the AEV 2.5 lift, but I've been so happy with this one I felt no need.

 

It will change just as much as adding 2" lift springs.

 

To answer your question. Leveling kits are safe.

 

Tuff Country 2" / 1" level kit. 285/70/17
Service manager at jeep dealer advised me to do the 2/1 level instead of 3" lift with this tire setup. He is very knowledgeable in lifts. He knew I wasn't buying mopar lift from them so he wasn't biased in recommending what I needed he did recommend using a level kit with metal pucks instead of softer plastics.

 

Interesting that he said to go with metal pucks. At the 4WD outlet, I also got a recommendation to go with the leveling kit, but when I asked about metal vs. plastic, he said to go with the plastic.

I've got 40K miles on my TF leveling kit and also no issues to date.

 

This.... As for geometry there is always compromises on a jk even stock.. Many people praise and "lcog" build but i dont know really anyone who has gone all out to achieve such. Theres soooo much more to geometry than just lift height..

 

But that wasn't the question addressed in his earlier post.

 

Been running teraflex leveling kit for 1.5 years now. No problems.

 

Of course it is. Safety of a road-going vehicle is absolutely dependent on suspension geometry, and to compromise suspension geometry can make a vehicle less to drive on the road. It may become "unsafe," depending on where you draw the line between "safe" and "unsafe". IMHO a JK is borderline "unsafe" as it rolled off the assembly line, and anything you do to make it less so definitely risks it becoming "unsafe". And BTW by "unsafe", I don't mean the Jeep driver is more likely to be injured in a crash; I mean the Jeep driver is less likely to be able to control the vehicle to prevent a crash in the first place. Statistics won't capture that, and without regard for demographics and a serious analysis on the topic, there's pretty much no way to statistically validate any claim that a JK is more or less safe than any other particular vehicle in terms of the ability of the driver to avoid accidents, so this is just conjecture (somewhat informed conjecture...) on my part.

 

I rest my case on your 3rd sentence: