CPP pitman arm failure beware!!!

[rockytopper R.I.P 5-13-2017]

Thought I would share this incase anyone has purchased one recently. We got called out on other site LOL for not sharing so here it is.

http://www.trifive.com/forums/showthread.php?t=168354

[WagonWonder]

I read some of that stuff over there. I noticed some didn't seem to want to be involved and some, well went over the top. I noticed CPP is involved too.

[WagonWonder]

Thought I would share this incase anyone has purchased one recently. We got called out on other site LOL for not sharing so here it is.

http://www.trifive.com/forums/showthread.php?t=168354

What I found interesting about the "call out" the person doing so said he visits here too. If he looked to see if it had been mentioned here and didn't find any results, why didn't he go ahead and mention it then?

[chevynut]

Wow, that could have been serious so it's a good thing the poster found it before he went for another drive.

I thought it was kind of entertaining reading that thread and watching all the "armchair quarterbacks" do their thing. Everyone has their own explanation of what happened, and their own solution. I have a stock original tri5 pitman arm right here by my desk. It's not welded, just staked in place like one of the CPP arms they showed a picture of. So is a weld better? Why did it work just staked for 60+ years?

First of all, there's not that much stress on that ball. The highest stress would be while turning the steering wheel with the car stopped and tires scrubbing the ground.

I don't know for sure what the root cause of the failure was, but it looks like the intrinsic design is fine, same as stock. I'd have to see the parts to tell for sure but what I see in the pictures is a cold weld or a fracture in the weld. It even looks like they ground the ball stud down to make a groove for welding. How much better could the design be? The stud really should fit tightly into the hole, which is probably what really caused this failure. The loose fit most likely allowed movement of the stud which caused the bad weld to break. IMO this is a tolerance issue or someone used the wrong stud in that arm. Maybe the material used was wrong, and it is not easily weldable.

If a stock pitman arm can last 60+ years without being welded, then welding clearly isn't necessary. A good, tight fit between the stud and arm is what's needed. Staking and/or welding is only to retain it. I'm surprised that nobody brought up heating the arm while welding affecting it's strength. That's what they usually say when something is welded and wasn't originally. I've had guys say I shouldn't be welding on the frames because that's a bad thing to do. :p

I also always find it amusing how guys badmouth Chinese parts and claim that only US made parts are any good. I've seen a lot of crap made in China, but I've also seen a lot of crap made in the USA. US workers themselves don't have any more inherent interest in quality than Chinese workers, in fact the opposite may be true since China became the worlds largest manufacturing location. Sure, China has made a lot of crap, but their stuff is obviously getting better just like Japanese junk in the 50's and 60's became world class in decades to follow.

I do think CPP should get to the root cause of the problem, figure out when things changed, and issue a recall if this isn't an isolated incident. Seems like one of their designs with the shoulder on the bottom is the best....I wonder why they quit doing it that way.

[chevynut]

What I found interesting about the "call out" the person doing so said he visits here too. If he looked to see if it had been mentioned here and didn't find any results, why didn't he go ahead and mention it then?

They're afraid of getting chastised for participating in this site. Some feel like they're "married" to the site and going elsewhere is "cheating". There's still guys who won't leave CT. :p I think a couple of them left here because of the political discussions that they didn't like because they're liberals. :D

[Rick_L]

A video which demonstrated the fit of the ball in the pitman arm was posted. It looked to me like there was .030"-.060" of clearance. I'd say that was a huge contributing factor.

Also, the photos posted of the staking showed that at least that example had superficial staking at best. You have to move some metal not just mark it.

Also it appeared that the welded examples possibly didn't have any penetration, and likely didn't have any kind of groove prep prior to welding.

It likely takes a combination of both fit and poor staking or welding to have a failure.

I hope CPP takes care of this. But a company that won't communicate to you about a back order probably won't unless forced to.

In the meantime, there are plenty of stock pitman arms.

[chevynut]

A video which demonstrated the fit of the ball in the pitman arm was posted. It looked to me like there was .030"-.060" of clearance. I'd say that was a huge contributing factor.

I agree, and probably root cause of the failure.



Also it appeared that the welded examples possibly didn't have any penetration, and likely didn't have any kind of groove prep prior to welding.

Not sure I agree with that. Here's the pic. To me it looks like either there was a bevel ground on the stud, or the weld broke at the edge of the HAZ. If the stud had been pressed in, this would not have happened imo.

http://www.shannonrichardson.com/57chevy/pitmanbroke.jpg


It likely takes a combination of both fit and poor staking or welding to have a failure.

IMO if it was just a good press fit, it would probably not fail. The staking or welding just keeps it from working out of the arm.


I hope CPP takes care of this. But a company that won't communicate to you about a back order probably won't unless forced to.

Yes, they sure need to investigate and take action if this isn't an isolated incident, which it might be. If I was a customer and didn't want to mess with them or hassle with a return and not know if you're getting a better part, I would check out my own part. Who knows how long before they do anything, if they ever do. I would grind the weld off and drive the ball out if it doesn't fall out. If it's loose, I would just get a good one elsewhere. If it's tight, I would grind a bevel on the stud, press it back in and weld it. It's not going to fail if it's tight and the weld is decent.


In the meantime, there are plenty of stock pitman arms.

And at least some of those are staked only. I removed one when I built the gasser frame and I had to press it out. We used a heim at that location.

[CPPTECH]

Thanks Guys, I am going to post what we posted on the other site here as well.

We are currently working on this issue and are equally very concerned. Since we
learned about this issue on Jan. 2nd we have been working as quick as we can to
learn as much as we can. To date we have quarantined all the inventory on hand
and started a thorough inspection process of each Pitman Arm one by one.


Additionally our engineer is and has been conducting random test. This
test also includes used Pitman Arms off our own test cars that came from the
same current inventory, some with over 4K miles on them. These inspections and
test results along with the history of this item will guide us as to what to do
next. We have great concern and are working quickly to understand the facts so
we can move forward with the correct response.

It should also be noted
that the current inventory we have on hand we have been selling since early
2015, and until now we have had no reports of failures or any issue similar in
nature. We are not trying to down play this in anyway, simply stating the facts.


Regardless of the test results, engineering has a plan to rework all the
Pitman Arms we have in stock by replacing the pressed in ball stud with a
properly sized stud and tig welding them at both the top and bottom.

We
will be back here with updates as we have more information to offer, in the
meantime if you or anyone you know has a CPP Pitman Arm, please encourage them
to contact us so we can document who has our products as we work thru this
process.
Feel free to PM Me, Email info@classicperform.com (info@classicperform.com) or call
800-522-5004

Thanks again,
Aaron Strietzel
aaron@classicperform.com (aaron@classicperform.com)
Classic
Performance Products Inc.
378 E Orangethorpe Ave
Placentia, Ca.
92870
www.classicperform.com (http://www.classicperform.com/)
714/522-2000 ext. 125

[WagonWonder]

I have little to no experience in joining metals by TIG but I understand the process. My question for those in the know; if materials (metal) are not of the same kind, how well does this work? I'd guess the ball is a better grade of steel but the arm itself looks like a casting. Can they be joined safely?

[Rick_L]

Yes they can be welded successfully. This is a steel casting, not cast iron. If the ball were very high carbon content, that wouldn't be good, but I doubt that it is.

As discussed, the fit puts the weld in greater stress than it would if the fit is correct. The fit should be the primary means of rentention, and any welding or staking should be secondary.

[Rick_L]

chevynut, I guess I missed those photos showing the weld, or forgot I saw them. There is indeed pretty clear evidence of a bevel weld prep.

[Rick_L]

A former member has posted on the trifive CPP thread expressing concern about welding high carbon steel to cast steel, in a reply directly to CPP. Something I mentioned in an earlier post. Curious that he'd do that to say the least.

Not caring to post there and confront either, I'll comment here. CPP said that the pitman arm ball is 4130. While that's not low carbon steel, it's certainly not "high carbon". It can be welded to the cast steel with no problem using ER70S2 or ER70S6.

As we've already discussed, the fit is what CPP should be looking into. I.e., what was specified, and what was used. At this point we don't know if they had an engineering problem, or a manufacturing quality problem (or possibly both).

With a good fit, the weld's strength is not really an issue at all.

I will give CPP some credit for the response so far. They published a drawing on the other site but it had no dimensions and was otherwise incomplete. But it's not their job to have us review their drawings - their job is to make this right. I hope their engineer has a decent test plan and test facilities.

[BamaNomad]

Who would like to be CPP's next 'test subject'?? :)

[WagonWonder]

I sent mine back today. No thanks.

[markm]

I use the pickiest front end guy with the best rep. in this part of the world. Both of my cars still have the originals. Do they sell that many replacements.

[chevynut]

Being "picky" doesn't necessarily mean a guy knows anything about the proper construction of something like a pitman arm. I'm betting he would have bolted that CCP arm on with no questions, just like lots of other guys have done. Anyone can overlook something like that.

And being original doesn't necessarily make a better part. That's why people replace original parts on these cars. I saw one CPP arm that imo was a better design than original as the stud went in from below, with a shoulder on it. It can't come out.