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Yet another Pitman arm failure... with Cognito braces

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62K views 40 replies 22 participants last post by  mtb rider  
#1 ·
The other night I pulled into my apartment parking lot, started to make a turn to back into a parking spot and I heard a very loud pop from the front end. So I stopped to look what it was and realized that when I jumped out of the truck that my steering wheel turned unusually easy. I crawled under the to find my pitman arm ball joint had sheared in half and was about 4 inches from where it should have been. I went upstairs and got Devin (83gmck2500) and we proceeded to kick the tires straight enough to get the truck in the grass out of the way.

Today I had a chance to dig into the truck a bit more to see what had happened. I dropped the sway bar down and took the Cognito brace off of the pitman arm. I used a 2 jaw puller to pull the sheared end of the center link and attempted to take the pitman arm off. There is not enough room to get a puller on the pitman arm due to the cross member that is in the way.

I took a look at the Cognito brace and realized that it was bent on both ends. It seemed that the heim joint tried to pull itself through the brace. It also bent the heim joint as well. Here are some pictures of the process.

I ended up pulling the steering box to get a better approach on getting the pitman arm off... And I'm trying to figure out the reasoning for this to happen.
 

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#5 ·
my braces bent as well. When i realized i noticed my centerlink was bent also. I actually just ordered a new set of braces and centerlink from Chad at alligator.
 
#6 ·
Does anyone know why they are breaking or bending? I'm thinking about taking mine out.

When I installed mine it seemed like you could actually put a lot of extra stress on the joint if they are improperly installed. By tightining the 2 jam nuts on the heim joint you could pre stress it one way or the other if your not carefull.

Did anyone else notice this or am I wrong?
 
#9 ·
The suspension is set at the Fabtech specs (Set at how I got it after it was lifted) plus 3 turns on the torsion bar bolt
 
#8 ·
I think in my case, the pitman failed (sheared) then the braces tried to hold the pitman and center link together... and didn't end so well. I'm still trying to get a hold of Nor-Cal Nick to get his take on what has happened since I bought the braces from him.

When I put the braces on the truck, I put them on loose and cycled the steering checking for any binding. Then I snugged up the bolts a bit and cycled the steering again. Lastly, I tightened the hardware and checked the steering for any binding or obstructions. Everything looked great until it went pop!
 
#10 ·
I hear more bad than good about these braces.

Id just go with lifetime warranty idler and pitman arms IMO

Thats what I just did, they should be at the house today and ready to put on :D
 
#14 ·
3 turns on the torsion bar bolts won't hurt any thing. All it does is put more force on the torsion bars resulting in raising the vehicle a slight amount and it also stiffens the ride a bit. It won't result in more wear on the steering components. What causes the wear on the steering is the larger and wider tires on lifted trucks.
 
#33 · (Edited)
The higher the static ride height the more angle of attack on the tie rods which puts more pressure on the idler and pitman arm. Braking, steering and other daily driving excersizes work harder the more angle that the tie rods push up on the centerlink. In a perfect world the tie rods would be at or near neutral so that the load would be pushing the centerlink stright in and not "rolling" it up. The same goes for the CVs. IIRC any more than 15-20 degrees is where the problems start.
 
#16 ·
Thanks to mreeves23 I got a new GM pitman arm (shipped quickly) yesterday in the mail. Today, I installed the new arm, put the steering box back in the truck, and hooked the lines back up. I started the truck up and cycled the steering... no leaks. After everything was double checked for being tight I went out on a test drive and everything is back to working condition.

I left the Congito pitman arm brace off, because it was mangled from the break. The idler arm brace was still alright, so I left it on the truck. I'm also going to go back in a day or so and check all the connections and bolts for being tight.
 
#19 ·
Could the heim joint have bound up or the arm come in contact with another part?
 
#21 ·
I talked with Chad at Cognito on friday and here is a summary of what he had said.

The first thing out of his mouth was "do you have Moog arms on you truck?" I guess that they have had this same problem with mainly Moog arms. I sent him pictures of what had happened (the pics that I posted here) and he said that it looks like I had the braces installed correctly and it is not likely a problem with the braces. I asked about the recommendations about worn parts:

"If the worn parts have approximately 40,000 miles or less on them with a close to stock size tire, they probably will not have to be changed. If the worn parts have approximately 20,000 miles or less on them with larger than 33” tires, they probably will not have to be changed. If the parts have more miles than that on them, it is recommended to replace the pitman and idler arms with factory units and add the Cognito Motorsports Pitman and Idler Arm Support Kit."

His response to the recommendations was that if there was noticeable ware on either pitman or idler arm that it is advised to replace them. Mine did not show any signs of ware so I did not replace the before the install of the braces.

He asked me to send him an email with a list of things that are wrong/broken/bent and he is going to try to get me the parts needed to "get me back on the road". It sounds like that will be at a discounted price or free... but im not sure which one.
 
#23 · (Edited)
I had the cognito braces on with a SuperSteer unit from Henderson's Line Up also. I installed new moog pitman and idler arms and cognito hd tie rods at the time of the install as well. I did not install the weld in support piece tho. I tore apart the cognito braces by driving in 4x4 on the highway. Step on the accelerator and the truck veers hard left. This did this for awhile then pop. That was it. Needless to say I tossed the cognito braces and just went and got this setup (still using the Supersteer unit tho).


http://www.exaxt.ca/steering_assembly.asp

Someone talked about the above kit before on here I believe. I have had it and it works WELL. This was my last step with the truck before I have the time to put a 4-link Dana 60 up front.
 
#24 ·
I had the cognito braces on with a SuperSteer unit from Henderson's Line Up also. I installed new moog pitman and idler arms and cognito hd tie rods at the time of the install as well. I did not install the weld in support piece tho. I tore apart the cognito braces by driving in 4x4 on the highway. Step on the accelerator and the truck veers hard left. This did this for awhile then pop. That was it. Needless to say I tossed the cognito braces and just went and got this setup (still using the Supersteer unit tho).


http://www.exaxt.ca/steering_assembly.asp

Someone talked about the above kit before on here I believe. I have had it and it works WELL. This was my last step with the truck before I have the time to put a 4-link Dana 60 up front.
That kit looks real nice, and seems the address all the issues. What does it cost?
 
#25 ·
From my experiences as well, I have not had any luck with moog or any aftermarket steering components especially idler and pitman arms. I always stick with genuine GM arms. I have found the moog arms to be looser and wear much quicker than the GM. Also, heard of a few guys breaking them very similar to what you have done. I do recommend GM steering components for sure with the braces. Hopefully you get the brace and parts that you need to get that portion reinstalled!

The exaxt kit appears to be a nice kit, but as others have stated it does change the geometry of the steering system since it uses a straight centerlink.
 
#27 ·
Pitman arm update

I got a reply back from Justin at Cognito about Mike and my pitman arms.

"Brandon's OEM pitman arm. If he was turning the steering wheel to the right when the stud broke loose, then the break happened in the forward to back direction which is the same direction the PISK provides support when the steering is pointed straight ahead. BUT, there are serious marks on the housing that indicate the stud was flexing severely, enough to hit the housing, which could have only happened before the PISK was added. So it appears that a stress fracture may have already been present at the time the PISK was installed.

Mike's MOOG pitman arm. If he was turning to the right when the stud broke loose, then the break happened in nearly the left side to right side direction which is not the direction that the PISK supports when the steering is pointed straight ahead. There were no marks on the housing and apparently this pitman arm was new when the PISK went on it. It appears to me that the pitman arm may have just had a flaw."
 
#29 ·
Nick,

I was waiting for this reply from Justin from Cognito before I put the new braces on... and I want to thank you again for all of your help and support through all of this! I think now, after having some time to think about the situation and after reading Justin's results, I think the braces will go braces on... my theory is that the pitman arm was just wore out.
 
#31 ·
Nick,

I was waiting for this reply from Justin from Cognito before I put the new braces on... and I want to thank you again for all of your help and support through all of this! I think now, after having some time to think about the situation and after reading Justin's results, I think the braces will go braces on... my theory is that the pitman arm was just wore out.

I think Copter is coming out to the shop this weekend and we will try and get that video up on the steering box I talked about on the truck we had here before the holidays.
 
#34 · (Edited)
I agree with the sentiment that the Moog arms are bad and may have contributed to the issue. If that is a moog pitman i am not surprised at all. The last Moog pitman arm I ran on my truck kept loosening up on the steering box spline. Eventually the splined shaft extended past the arm and i junked it. A local shop also experienced the same problem from what they told me. Also the Mood idler and pitman use course threads on the shaft unlike the factory parts which IMHO is another weakness.

I have bent my idler brace in the past. My 4lb mallet corrected the problem though. In fairness, I also bent two super diesel centerlinks, the factory idler brackets, and a stock centerlink as well.....:) Perhaps using a stronger alloy like chromoly would make them a bit stronger?