Torshion Bar Adjusters

[EddieS'04]

I have an odd issue. I took a measurement and my front has sagded some over the years. I raised both tires off the ground, to unload the torsion bars. Jacked from the center of the motor frame.

I was going to raise the front 1/4" to 3/8".

Started on the driver side. I lubed the bolt first. I was going to try 2 rounds and remeasure.



I watched as I turned the first round. The bolt turned freely the full length. Started the second round. The bolt snaped between the adjuster plate and the torsion bar. The bolt, still turns freely in the adjuster plate. So I can remove it. I wont have to drill it out.



Im very familiar with torsion bars. I have had them on other cars. All I had to do was get the tires off the ground. To relax the bar tension.



Any Ideas' on this issue? Never had an adjuster bolt snap on the torsion bar side. I have had them snap in the threads, from being seized. I adjusted the driver side years ago. To get rid of what we call the ranger lean, 'cause of the fuel tank weight.



I can repair it, with more work. It is a murphy's law thing. I was thinking, with the tires off the ground. Would it make a a difference on the T-Bar load? If I put a second jack under the lower control arm? To reload a small amount tension, on the t-bar?

That doesnt' make sense to me. I have to now get my puller and compress the t-bar. To install a new bolt.



Im going to buy 2 bolts just in case the right side snaps also...LOL...not funny really. Might have just been a bad oem bolt. If it had snaped while driving. The left front tire would have fallen up into the fender well.



I just thought I would toss this out there. In case a member has some info. Now I have to wait untill I can find a ride for bolts. Last 5 years, is the first time. I only have one car...I wish every day, I hadnt' sold the 'stang. New owner totaled it after 4 months..:sad:



Thanks for any input......:banghead:

 

[EddieS'04]

Update:

As for the oem bolt. It has been cracked half way across, for awhile. Signs of rust between the 2 halfs. Glad it didnt snap driving @ highway speeds. A sudden drop of the left corner, would have locked the tire into the upper fender well. Possible flip or roll the trac. Its' way out of warranty but, Im going to turn it into NHSTA and give ford a copy and pictures. I will pull the right hand side bolt out for inspection. Probably put a new one in there also.

This was an accident waiting to happen. I will take pics for this board.



Got a ride and found some regular bolts. 12mmx1.75 @ 10.9 grade hardness. Oem's are 10.8 hardness. I need to grind a ball tip on the end. IMO, 12mm is small diameter, compared to others I have worked on. My '73 340 Cuda torsion bolts were 3/4" diameter @ grade 8. As were 2 other chrysler products I owned.



So I will finnish tomorrow. Dark already. Plus Im' debating drilling and retaping the plates to a larger diameter bolt size. Any opinions on that??

 

[Yardsale]

Plus Im' debating drilling and retaping the plates to a larger diameter bolt size. Any opinions on that??

This must be a low occurrence failure as I don't recall any reports of this. I think you don't know what caused the bolt failure. I doubt it is an inherent design flaw, although it could be a defective part, but I suspect that the bolt was somehow damaged. I don't think this warrants a alteration and potential weakening of the adjuster (a failure in the waiting).



Liability (civil and or criminal) and insurance. When you alter a vehicle part, assuming an inspection reveals the alteration, you could be liable for any failure and associated ramifications. If there is high dollar repair or injury, or death, there will probably be an inspection to determine cause. If it is determined that the cause is a result of that alteration, or it can be claimed it was the result of that alteration, your insurance company will probably deny coverage.



Not sure it's worth it.

 

[Doctor CAD]

There is no grade 10.8, did you mean grade 8.8 on OEM?



Grinding on the bolt will heat it and remove some of its hardness. I wouldnt do it. Just get regular replacements at a Ford dealer.

 

[EddieS'04]

There is no grade 10.8

Stamped right on the head, very plain 10.8....

Just get regular replacements at a Ford dealer.

Local dealer not in stock. So I bought bolts in the same hardness. Im just grinding a slight taper on the tip. The oem's have a ball tip. So it will center in the key.

I trust the bolts, I bought.I just have a hard time understanding the small diameter. There is alot of pressure against them. 12mm is slightly smaller than 1/2". I have seen larger on sedans.



I installed the new one last night. Then left the trac on stands. I will pull the right side bolt out for inspection. I dont trust it. My trac has always been @ front oem height. So this was a fractured bolt from the factory...IMO. It only took 2 rounds to level it, with a full tank, when new.



What started this job was. I noticed my - camber getting worse. When I looked under. The lower control arms were 1/8" from touching the bump stops. They used to be 1/2" or more. Raising it some will afect the + camber..Best to get alignment after.

 

[swshawaii]

Wow Eddie, never heard of them breaking there. Agree that M12 torsion bolts and the head size seem very small for the amount of load on them.



Interested to see pics of the failure. Did you check out the link I emailed you? That site is awesome and covers every make, model, and year from 1954.

 

[Yardsale]

 

[Yardsale]

 

[Yardsale]

 

[Yardsale]

 

[Yardsale]

 

[Yardsale]

 

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[Yardsale]

 

[Yardsale]

I think that bolt size is fine for the use for three reasons. First, think about what it does - it takes a compression load. Second, I don't know of this failure being common. Third, the size was selected by engineers for the system (and engineers never error .

 

[H D]

Yardsale, what do you think about the size of the torsion bolt?:bwahaha:

 

[Yardsale]

Far too much!



Damn mobile update.

 

[EddieS'04]

Here is the bolt. You can see the stress crack. It is the rusted area. About half the diameter.



Yardsale, it may not be common. But this is the smallest diameter bolt I have seen. On a torsion bar system. Some of the older crysler products used 3/4" sae fine threads. On cars lighter than our tracs. Stronger and more control over, how much one round would change hieght.



One thing I found today was the left torsion bar. Is not centered. The back side of the t-bar key rubs the inside of the frame. This makes the adjuster bolt at more of angle. The right hand side has 3/8" clearance. So the adjuster bolt and the puller indent is lighned up with the holes.

Trac has been side swiped on the right. Just cosmetics. Never been crashed, unless it fell off the line and bent the left torsion bar. I never hit a drastic pothole. Soooo!



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[Brett Stoner]

One of my torsion bar bolts broke as well when I was adjusting it last year. Took it out and bought a couple 10.9 grade, M12 1.75. Grind the end to a round point to fit in the pocket. Also ran a tap through the plates to make it go smooth. Worked great and cost a couple bucks at the local Fastenal.