New Rockkrawler Severe Duty Long Arm System

[Jeff Weston]

First, let me say right up front that I do not have this suspension, nor do I know anybody personally who does. Like most others on the net, I have heard of the now infamous case of the one guy's front RK suspension failing and him wiping out. This opininion is based solely on the article I just read in this month's 4WD&SU magazine.

According to the article in said mag, this is a new and improved kit with long arms, using a tri-link setup in the rear and a radius arm setup up front. From what Blaine explained to me about the loads heim joints are designed for and the fact that there is no beefing up of the upper frame mounts still makes the rear a scary proposition.

What is more troubling than the rear is the new radius arm setup they are running up front. Instead of traditional radius arms which are fixed at the axle and pivot at the frame, they have come up with something a bit different. The passenger front arm is just a single control arm (not fixed at the frame). The driver side arm is similar, with the exception of a "torque arm" which mounts to a bracket which mounts to the lower shock mount. This single arm and bracket is the only thing keeping the front axle from wanting to fold under.

Clearly, with only a single arm, they are trying to reduce the binding and stress on the control arm mounts and allow easier cycling of the suspension. I have seen the same concept for custom early Bronco radius arms. The difference with this particular setup is that when you hit the street, a very large bolt is installed, making the articulating radius arm rigid again.

Somebody tell me if I'm Chicken Little and proclaiming the sky to fall, but doesn't this setup seem as, if not more, unsafe than their first setup? It just seems fundamentally weak (really putting a twisting force on the axle tubes and welds when you lay into the brakes) and any failure would be catostraphic.

Thoughts?

Jeff

[mrblaine]

I have a lot of thoughts, but as I was sent the pics of the first catastrophic failure, I was sworn to not discuss them by the owner of the rig.

You are just another ride in the amusement park of my mind.

[Jeff Weston]

Blaine,

I respect your confidentiality and apologize for mentioning your name in this post. It is my understanding that this is not the same kit that Andy (he was on the Jeep-TJ list) was running when he had his problem.

What I was referring to was simply the article and pics in 4WD&SU on the new kit. It simply seems dangerous for the street and certainly should have the appropriate warnings clearly stated in the article.

Again, sorry if I stepped on any toes.

Jeff

[Makatak 350]

I was a little shocked at some of there designs too??? Even though there rods for the radius arms and tri- link are solid they appear to small and weak compared to other designs i have seen.
Besides, what does an albany (new york) based company know about building suspenions for rock crawlers???? Are these guys transplants from out West???? Personally i have seen some of these kits and am not sure i would buy one.

[ChrisK]

They are on the list of companies I will never do business with. People seem to be in 2 camps about them. Hate them or very strong supporters. I have personally read too many bad stories about component failures of their parts and extremely poor customer service that they will never get a penny from me.
I once raised the question about the number of failures in their relatively short company lifespan to one of their supporters and he said that RE and Tera had more. No facts. Just said they had more and its just that nobody knows about them. Their designs seem amatuerish and without proper engineering or knowledge thereof.
They also seem to have a knack of suing people that had their design and now speak ill of them.

Chris

[underwood]

Im not bashing here.

Went wheeling with the white wrangler in this months build up in JP.

Could not speek for strength however the flex was terable.

The anti squat is dangerous. Almost roled driving on the street, turning sharp.

It wa RC desigens.

[Makatak 350]

IT FLEXS AS BAD AS ARE SPELLING AND PUNICUTION

[underwood]

don't now if it's that bad

The flex that is.

[AprilzWarrior]

My buddy runs this "new" RK LA Kit I didnt install the Kit, Rear Tri-Link that I installed w/PICS (if you like to see) and I hate it on his ZJ.

Personally, I installed it and tested it... Scary stuff. The Anti Squat can get ya killed, The rear of the Jeep wants to "dive" on turns and leaves the driver feeling like the vehicle will slide out.

There was quite a bit more flex from the Tri-Link, but RK sends out washers...thats right washers for shims because the Rod ends are not wide enough for the Stock Upper Control Arms mounts on the body. Furthermore the UCA mounts must now support a lateral stress which they were never designed for.

My way around this is to weld into place 1"x1"x 1/4" angle iron from Bracket to bracket in the rear up near the Sway bar. Im sure its not and end all because eventually the UCA mounts will tear off.

Take this as you will and Im not bashing either, just throwing some opinion out there.

AprilzWarrior

[mrblaine]

Originally posted by AprilzWarrior
My buddy runs this "new" RK LA Kit I didnt install the Kit, Rear Tri-Link that I installed w/PICS (if you like to see) and I hate it on his ZJ.

Personally, I installed it and tested it... Scary stuff. The Anti Squat can get ya killed, The rear of the Jeep wants to "dive" on turns and leaves the driver feeling like the vehicle will slide out.

There was quite a bit more flex from the Tri-Link, but RK sends out washers...thats right washers for shims because the Rod ends are not wide enough for the Stock Upper Control Arms mounts on the body. Furthermore the UCA mounts must now support a lateral stress which they were never designed for.

My way around this is to weld into place 1"x1"x 1/4" angle iron from Bracket to bracket in the rear up near the Sway bar. Im sure its not and end all because eventually the UCA mounts will tear off.

Take this as you will and Im not bashing either, just throwing some opinion out there.

AprilzWarrior

Not sticking up for anyone here but the loads are not lateral on the UCA mounts. They are still mostly front to rear. The issue is that the mount was never designed to handle the additional stresses placed on it by the elimination of the track bar.

The tri link is still a triangle. If you push one point to the side, the other two compress on one side and extend on the other. The load is only slightly lateral and mostly front to rear.

Currie has known this for a long time and makes braces that weld on over the top of the mount back to the frame.

[StealthTJ]

Here's a photo of the Currie brace. Though you can't see if from the angle of the photo, there is a piece, on the top, that ties the top of the brace to the top of the frame rail.
It extends quite a bit forward of the foreward end of the stock mount.
It also ties the lower end of the stock mount in the the frame rail.
It really adds a lot of beef to the stock UCA mount.
The Currie brace is 3/16" thick.







Fred

[quadna71]

I?m running their ?new and improved? kit. I was hesitant at first but couldn?t pass up the price. First install appearance. The arms are plenty beefy ? I?m not too worried about them. While listed as a LA kit?in the late model TJ?s the further rear position of the transfer case skid causes a shortening of the rear arms. The bracket that provides the center-frame mounts for the lower arms center around the skid nutzerts?and then is stitch welded into place. There were plenty of threads to keep the pinions angles properly even up into my tall springs ? and I haven?t hit the tank skid yet.

My single biggest issues with it I think are the fact that the rear upper tri-four link arms are pretty short. If they were mounted to a more forward point (instead of the OEM mount) then I think it would be better. But it seems that the rear is pretty hard pressed to flex a lot. They do supply some ?? brackets to get welded up to the factory upper mounts ? but are sort of a hassle to get situated. I may be better off just fabbing them over myself. I can get the rear to flex much more with my front swaybar still connected ? but that?s not going to happen. Sort of makes it an obligation to get an anti-rock up there now. For now I?ll head that direction to keep the lift working smoothly ? but I?m already tracing out a new mount for some longer upper arms ? and then just replacing them with some home-built ones. Seems a pain in the arse for an out-of-box kit?but it?s a learning experience for me.

My first lift was an RE short arm ? their 4.5?and it served me well. But my height had lent to a rough ride on the jeep. I?m the kind of person that?s never happy with a given setup ? so I?m sure I?ll be swapping out this and that over time. At least if I change my mind later the stitch welds are easily zipped through. But for now I feel this kit is far and away a better riding, handling, flexing, and all around suspension than my previous setup.

I have some photos that I?ve taken of it in various angles?from the mounts of the arms to a few shots of it on a ramp. Let me know if you want to see them close up. I appreciate all the comments on this lift?the critical ones will just make me look closer and either recognize/agree, disagree/clarify, and/or fix them to help the suspension improve.
Chris

[Jeff Weston]

Post up the pics. Also, make certain to use those brackets to beef up the factory upper mounts. The front sure looks like an improvement over the old style with the one radius arm on the driver's front. That little short arm connected to spring bucket or shock mount or whatever it was, looked a bit scary. That said, their lift certainly has undergone several major re-designs in what seems to be a short amount of time.

Post the pics!

[quadna71]

could only access/link these ones from work. i'll get the others on my other photohosts when i'm at home.
chris (mil lockdowns! )

[quadna71]

i'll have to snap more later. anything you want to see up close?
chris

[wildman4x4nut]

I'd like to see a better picture of where they are mounting the front upper control arm. From the picture it looks like it is almost mounted right on top of the lower. I can't see how that would flex good.

Thanks

[DsrtJeeper]

I'm slightly confused here. Is the main issue the fact that RK only runs one upper arm in front? I've been running a 4 link setup in front for about 6 months now. I love the nice flex, but I do realize the dangers.

I have pics here of two XJ's using RK's lift with supplied coilovers. The first thing I spotted in a photo was how far the rear of the XJ squatted on an obstacle. This in turn caused the front to lift and climb skyward. The other pics show various lifted XJ's driving the same line with much better manners. It is my opinion that energy spent seperating your front body from the axle is wasted energy. That energy should be moving your vehicle forward. The RK kit seems to unload terribly on the tri-linked XJ's.

Coming from the Albany area myself; I too have wondered how they obtain there rock crawling expertise. When I lived in NY; there was not one legal OHV trail in the state.

If you do a search at Pirate; you'll find a comical thread in which Jeremy from RK attempts to improve RK's image. There are alot of good points brought up including RK's supposed patent on their suspension design.

Speaking of coilovers....How can a company include these with their lift in generic form and expect them to work with all Jeeps? Anyone who has tried to dial in a coilover knows that there are very few setups alike.

[Jeff Weston]

Originally posted by DsrtJeeper
I'm slightly confused here. Is the main issue the fact that RK only runs one upper arm in front? I've been running a 4 link setup in front for about 6 months now. I love the nice flex, but I do realize the dangers.

This is an old post. The current RK setup appears to be a lot better than the previous. For what must've been a short while, the driver's arm was a radius arm formed using a small, short arm connected to the spring perch or shock mount or something like that.

Here's a pic that I that I found on the web on an XJ. The passenger side has a single arm and the driver's side has this. Unlike the RE radius arm which connects to the cast pumpkin mount (see the empty hole), this thing somehow bolted to the plate that the shock mounts to.

[quadna71]

Originally posted by wildman4x4nut
I'd like to see a better picture of where they are mounting the front upper control arm. From the picture it looks like it is almost mounted right on top of the lower. I can't see how that would flex good.

Thanks

the upper torque arm mounts to the axle in the identical locations that all other LA kits do - the factory mounts. the rear mount of the upper torque arm is just inside of the frame - and at the same height as the frame. i can see how the shock mounted upper arm in their previous designs would be flawed...but this design rotates/pivots the axle pretty well.
chris

[DsrtJeeper]

Doh!!! I didn't notice this was an old post. I wheel with several guys who run the new kit. It definately provides more than enough flex at the expense of coils popping out!

I've met three people in the local club who have since removed there RK LA kits for one reason or another. It seems that some have problems with the rear tri-link setup.

[mrblaine]

Originally posted by DsrtJeeper
Doh!!! I didn't notice this was an old post. I wheel with several guys who run the new kit. It definately provides more than enough flex at the expense of coils popping out!

I've met three people in the local club who have since removed there RK LA kits for one reason or another. It seems that some have problems with the rear tri-link setup.

At one point, RK was unable to understand that you don't load a threaded shank of either a bolt or rod end laterally and expect any result other than failure.

I still see some folks do it, but the shank is typically large diameter and heat treated alloy.

I lost respect for them as a company when they tried to argue the merits of poor engineering as a good thing.

Very similar to Rusty trying to convince me that tube is stronger than solid of the same diameter.