LCA pivot shaft and adjustable strut rod issues

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biggen59

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First time posting here folks.That being said,has anybody purchased the new LCA pivot shafts,and or adjustable strut rod kit from PST,and had issues with either one? Could not get the strut rod to line up,to the attaching bolt,at the LCA,(per instructions)Loosened the nut on the new pivot shaft,to gain a little play,and it started ripping the threads off of the shaft.These shafts seem to me to be much softer steel than the originals,and the "lock nuts" provided were of the "stick em in a vice,and crush'em till they're egg shaped variety"
Went ahead and installed the other side,and with a little creative burr grinding,on the LCA arms strut rod attachment hole,and the use of the factory nut from my old shafts,second,side went together,fairly easily.Anyone else had these issues,or am I the only one?
 
It's not anything that I have dealt with. If I were to buy adjustable strut rods there are other places I would go first (RMS). I've never had to buy new LCA pins.
 
Just thought I'd do myself a favor and replace the pivots,that was a mistake on my part.As for the strut rod kit,well I can deal with a little tweaking,production tolerances being what they are,and the kit from PST is pretty nice.I guess my biggest complaint here is that when I contacted PST about these issues,they pretty much told me that there were no issues,and weren't willing to replace the shaft.On the flip side,while building the front disc brake conversion,from Right Stuff,I discovered that the lower ball joints,had not been machined flat,where it mounted to the spindle.One call to Right Stuff,and a new pair were on my porch,in two days N/C.
 
biggen59 said:
First time posting here folks.That being said,has anybody purchased the new LCA pivot shafts,and or adjustable strut rod kit from PST,and had issues with either one? Could not get the strut rod to line up,to the attaching bolt,at the LCA,(per instructions)Loosened the nut on the new pivot shaft,to gain a little play,and it started ripping the threads off of the shaft.These shafts seem to me to be much softer steel than the originals,and the "lock nuts" provided were of the "stick em in a vice,and crush'em till they're egg shaped variety"
Went ahead and installed the other side,and with a little creative burr grinding,on the LCA arms strut rod attachment hole,and the use of the factory nut from my old shafts,second,side went together,fairly easily.Anyone else had these issues,or am I the only one?
Click to expand...


This just happened to me, but worse - the passenger side nut is so tight it started spinning the shaft and the driver side did just as yours, sheared the threads. After reading this thread I guess I'll know what to expect from PST.
 
Once upon a time long ago...........1995/1996, I was a starving college student working two part time jobs and going to school full time. To say I was broke was a understatement. I scrimped and saved until I could afford a front end rebuild kit for the /6 72 duster I was driving. The strut rod bushings fell apart before I got it across town to the alignment shop. Replaced them with moog and went back and it aligned okay. within 5000 miles it was all shot. I have never bought one single thing from PST since. maybe they have gotten better but does not sound like it.
 
I never had to purchase any new pivot shafts either.
But here's a situation that i think you might be having.
More than likely those new shafts of yours are machined off shore, in China.
Then i'll bet they are threaded in a metric size.
You stated your using the original nut, which is fine thread American standard.
Then your trying to put together American, and Metric, which ain't gonna go.
Just my 2 cents on your problem.
 
hemi71x said:
I never had to purchase any new pivot shafts either.
But here's a situation that i think you might be having.
More than likely those new shafts of yours are machined off shore, in China.
Then i'll bet they are threaded in a metric size.
You stated your using the original nut, which is fine thread American standard.
Then your trying to put together American, and Metric, which ain't gonna go.
Just my 2 cents on your problem.
Click to expand...

The new shafts were supplied with nuts from PST. These are, as described up above, a crushed nut. Or, intentionally deformed to act as a locking nut. It seems maybe the nuts were deformed too fr and the result is mangling the shaft threads.
 
hemi71x said:
Well then, you blue my theory out the window.
Click to expand...

But I'm sure China has something to do with my problem! They buggered up the SAE to metric conversion in their manufacturing... rounded up to whatever the mm measurement was.
 
Some of this is just the norm for scored nuts. The factory used similar nuts on the leaf spring U bolts. Look closely and you'll find a small rectangle stamped into 2 opposing flats. They go on a heck of a lot easier than they'll come off again. Using this type hardware in certain applications is all about safety.
I cant imagine PST having a person checking the quality of every part. Go/no go gauges are time consuming. Regardless... If the nuts they provide destroy the shafts they provide one or the other is out of tolerance. They should make it right.
In the end, Aftermarket is what it is. We have learned ( the hard way ) to reuse our OEM locking ring at the aftermarket fuel senders. I guess we should learn to reuse our original nuts at aftermarket lower arm pivot shafts also. Good luck
 
Hello,

I am sorry that I missed these posts. If the people that had issues with our product would like to PM their details I will work to correct the issues accordingly. As for the comment that jumps to the conclusion about product being an issue with China that is un-true as we have the pivot shaft machined
here in the USA as well as the strut rods.


Thanks
James
 
The original LCA studs use cotter pins as the locking devices to avoid this. Makes sense as these were intended to be removed and re-used as a service part as LCA bushing were replaced as service parts.

IMO.....this merits a re-design to use a cotter pin to avoid this issue; loosening the LCA pivots as part of other normal front end service procedures is the norm, and the LCA pivots should not require removing the LCA's and replacing them just for these simple procedures. Crush nuts should are not intended to be used for re-use threaded fastening; they will almost always do something to distort/damage the mating threads when backed off, unless the bolt is much harder than the crush nut.
 
FYI:
Not all year, make, model, Mopar automobiles use the cottor pin arangement on lower control arm shafts, pins, (whatever you personally refer them as)
All A body cars from the beginning, use a self locking nut on the threads of the shaft.
The cars that used the cottor pin on the shaft were early 60's B Body cars till sometime till the mid 60's.
After that they used the regular self locking nut. Same with the E body cars.
Cotter pin shafts, that use a castle nut, or others that use a self locking nut have got nothing to do with the op's situation.
But you don't interchange nuts from one style shaft to the other.
 
PST said:
Hello,

I am sorry that I missed these posts. If the people that had issues with our product would like to PM their details I will work to correct the issues accordingly. As for the comment that jumps to the conclusion about product being an issue with China that is un-true as we have the pivot shaft machined
here in the USA as well as the strut rods.


Thanks
James
Click to expand...

James,
Thank you for the follow up on the forum. I appreciate your defending the assumption of Chinese made products and am glad to hear you are sourcing US manufacture for the products you offer. With that said, a faulty product can originate from just about any country...and we were going after low hanging fruit in the blame.
I also acknowledge in my frustration I expressed a potential lack of resolution based on another member's experience, which not having yet had dialogue with you about the matter is perhaps a bit unfair. I look forward to discussing the matter here shortly.

I had the same experience as the OP at the beginning of this thread, that the crushed lock nuts, which are of a harder steel than the shaft (and the shaft being a much softer steel than the original pivots) and also perhaps deformed to be smaller than the thread diameter, sheared the threads from the pivot shaft. This is on one side of the car. The other side now has the nut seized on the shaft without being tight to the frame.
This is all very frustrating - as you know, there is only so much time in a day, money in the bank, and windows of time a car is allowed to sit in a rented work space. The fact that I have to do this over constitutes a major headache, and a a major setback.

Please let me know how this situation can be resolved.
 
There's a reason the prices are lower than other suppliers.
 
MrCuda68 said:
There's a reason the prices are lower than other suppliers.
Click to expand...

I do not really under stand what is meant by this as our pricing is competitive and also as a courtesy to the people of this board we offer the members discount. We take pride in our product and that is why I am trying to get the bottom of this issue. As for the pivot shafts I believe we are the only ones producing the original style as of now I know that there are 2 other companies that carry the greasable type.

Thanks
James
 
eholster said:
James,
Thank you for the follow up on the forum. I appreciate your defending the assumption of Chinese made products and am glad to hear you are sourcing US manufacture for the products you offer. With that said, a faulty product can originate from just about any country...and we were going after low hanging fruit in the blame.
I also acknowledge in my frustration I expressed a potential lack of resolution based on another member's experience, which not having yet had dialogue with you about the matter is perhaps a bit unfair. I look forward to discussing the matter here shortly.

I had the same experience as the OP at the beginning of this thread, that the crushed lock nuts, which are of a harder steel than the shaft (and the shaft being a much softer steel than the original pivots) and also perhaps deformed to be smaller than the thread diameter, sheared the threads from the pivot shaft. This is on one side of the car. The other side now has the nut seized on the shaft without being tight to the frame.
This is all very frustrating - as you know, there is only so much time in a day, money in the bank, and windows of time a car is allowed to sit in a rented work space. The fact that I have to do this over constitutes a major headache, and a a major setback.

Please let me know how this situation can be resolved.
Click to expand...


Let me look into this for you. Please pm your details (name and address) also was the issue you are having with the greasable or oem style pivot shafts?

Thanks
James
 
Jim Lusk said:
It's not anything that I have dealt with. If I were to buy adjustable strut rods there are other places I would go first (RMS). I've never had to buy new LCA pins.
Click to expand...

i believe RMS supplies PST with the adjustable strut rods..
 
Could not get the strut rod to line up,to the attaching bolt,at the LCA,
Click to expand...


i just installed RMS adjustable strut rods and they went right in like they were supposed to..


what exactly isn't lining up?? have any pictures??

DSC_0292.jpg
 
So you've discovered the difference between "metallic" and "non-metallic" locking nuts (commonly called Nylock). In the aircraft industry both are considered a single use fastener. The difference is the corresponding bolt is more likely able to be reused with non-metallic locking nuts (whether any fasteners should be reused is another discussion). Metallic locking nuts tend to tear up the threads on really good bolts of similar hardness, I can only imagine what one would do to a softer thread.

Best practice is to do any mock-up with standard nuts and swap to locking nuts after final assembly when the fasteners are torqued/cotter pinned/safety wired for the last time.

Perhaps PST could add a note to their instruction sheet recommending standard Grade 5 nuts for mock-up, and for a few pennies, throw a couple in their kits. And, although not visually correct Grade 5 Nylocks would be plenty adequate for strut rods, either end, allowing for easier future disassembly.
 
C130 Chief said:
So you've discovered the difference between "metallic" and "non-metallic" locking nuts (commonly called Nylock). In the aircraft industry both are considered a single use fastener. The difference is the corresponding bolt is more likely able to be reused with non-metallic locking nuts (whether any fasteners should be reused is another discussion). Metallic locking nuts tend to tear up the threads on really good bolts of similar hardness, I can only imagine what one would do to a softer thread.

Best practice is to do any mock-up with standard nuts and swap to locking nuts after final assembly when the fasteners are torqued/cotter pinned/safety wired for the last time.

Perhaps PST could add a note to their instruction sheet recommending standard Grade 5 nuts for mock-up, and for a few pennies, throw a couple in their kits. And, although not visually correct Grade 5 Nylocks would be plenty adequate for strut rods, either end, allowing for easier future disassembly.
Click to expand...

I hate referencing Wikipedia. Th last time I did was when making fireworks at home and I'm still looking for my index fingers... Here goes -

Elliptical offset nuts

Elliptical offset nuts is a catch-all category that encompasses designs known as oval locknuts[1] or non-slotted hex locknuts,.[3] The salient feature is that the threadform has been deformed at one end so that the threads are no longer perfectly circular. The deformed end is usually shaped into an ellipse or obround triangle. These are known as one-way nuts as the nut may be easily started on the male fastener from the bottom non-deformed portion, but are practically impossible to start from the deformed end. As the male fastener reaches the deformed section it stretches the threads of the nut elastically back into a circle. This action increases the friction between the nut and the fastener greatly and creates the locking action. Due to the elastic nature of the deformation the nuts can be reused indefinitely.[2]

Here's another much more in depth link
http://www.fastenerexperts.com/lock-nuts/
 
I dislike using Wikipedia as a sole reference as well. Mostly because it's full of BS!
 
hemi71x said:
FYI:
Not all year, make, model, Mopar automobiles use the cottor pin arangement on lower control arm shafts, pins, (whatever you personally refer them as)
All A body cars from the beginning, use a self locking nut on the threads of the shaft.
The cars that used the cottor pin on the shaft were early 60's B Body cars till sometime till the mid 60's.
After that they used the regular self locking nut. Same with the E body cars.
Cotter pin shafts, that use a castle nut, or others that use a self locking nut have got nothing to do with the op's situation.
But you don't interchange nuts from one style shaft to the other.
Click to expand...
I appreciate the very good info; thanks for posting. The comment on cotter pins was to make the PST shafts more 're-usable'.
 
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