4 link shock mount failure

[Darius]

Some of you know I installed a Ride Tech 4 link rear suspension in my GTX. I got this as a pkg along with my AlterKtion. After 14,600 miles this happened

 

[Darius]

This was the fix. Since these mounting studs are NOT hardened, we bought 3 1/2" hardened bolts and created a mounting support bracket to spread the load. Time will tell if it is better. Pretty piss poor design really, as you can see, the other one was about half way sheared as well.
Hard to get good shot, hope you all can see it. The bracket was welded onto the cross bar to give a bit more support to the stud. That is the theory anyway

 

[davek]

well that sucks that you spent the money and it failed. Nice fix. In all and all are you happy with the 4 link setup?

 

[Darius]

I DO like this suspension. I have NOT been easy on it either. I have quite a few miles on it since done. Twice I have had it on a 2 1/2 mile road course. On the way to that course (appx 400 miles one way) there are a couple of awesome country winding twisting hilly roads we obliterate on the way. I have also had it down the track several times (13.77 best time@ 103mph). Besides handling well in both of those environments, it is a dream cruise set up. I drove from Las Vegas to Sacramento in a day, 9+hours, and I was very comfortable the whole way(except for the hangover part)!

 

[davek]

was it hard to install? Mod or cutting? Bolt in setup?

 

[69b3rt]

It looks to me like the whole weight of the rear of car is supported by that upper shock bolt. It sure looks like the whole upper shock mount needs stiffening. It reminds me of the original shock crossmember getting a beating from using air shocks.

 

[Darius]

was it hard to install? Mod or cutting? Bolt in setup?

Did not have to cut anything as I recall. Just lined it up and instead of just bolting into the holes (which lined up nice) we welded it in.

I agree with 69b3rt, it is a lousy design and the overwhelming majority of the rear is supported by the shock/spring assy. They could have at least hardened those supports. Hopefully our fix will hold up.

 

[Kern Dog]

Well, the shocks are supposed to only dampen suspension movement, not support the car. I thought the aftermarket kits included a "weld-in" replacement crossmember ??

 

[66Satellite47]

I agree with Kern, what is the upper shock mount connected to?

 

[andyf]

I can't tell for sure but it appears that the car is supported by the coil overs which are anchored on a stud that is screwed into the upper bracket? If so, that is a fatally flawed design. A real engineer wouldn't design anything that stupid. If the car weight is going to be supported by a bolt it should be a double shear mount and the bolt should have a 3x or 4x safety margin.

 

[Darius]

There is a 1 3/4" crossbar that is welded very securely to the rear frame rails. The upper shock mount pivot supports screw into this bar very near where the original stock shock mounts were.

 

[66Satellite47]

On my 2100# tube chassis car, the rear coil overs were mounted to a 1 5/8 round CM tube with a 3/16" wall threaded bung through it, Grade 8, American made 7/16" fine thread bolt with the proper length shank to match the bearing.