How to safely install trunk torsion bars

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Gary

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Hi - This thread is designed to gather into one thread the information needed to safely install trunk torsion bars while keeping all your teeth in your mouth.

There are 5 or so threads discussing topics like "how many torsion rods should be installed" and "which notch to set the torsion rods into to provide the sufficient opening power", and "should I add a second torsion rod if I am adding a rear spoiler". If there is a thread that concisely shows "How to Install Trunk Torsion Rods", then I missed it. Please send me a link if you know of it.

I've watched some YouTube videos from guys installing trunk torsion bars on Cougars, Comets, and some of the 65-69 Mustangs but nothing in the 71-73 era. The ones I saw, they typically had to fabricate a tool or buy one online to safely install the torsion bars. There is a L-shaped tool with a u-shaped slot for the rod and a drilled hole for inserting the torsion rod but it wont work on this style of torsion bar. Then there are the guys who use a pair of vise-grips and muscle the torsion bars into place. One of those guys went to the hospital after the vise grip lost its grip and hit him in the face. However, none of the tools I've seen appear to work on the 71 torsion bars I have. I'm attaching pictures of the torsion bars and the hinge design.

I've concluded I'm not going to use vise grips. There must be a plethora of knowledge out there on how to safely install trunk torsion rods like the ones below.

I have a 71 coupe but I am adding a rear spoiler so I am going to install 2 rods rather than one to keep the trunk level and provide sufficient lift.













 
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Looks as though the original tool has been replaced with a more robust one. I sure wish I'd had one of these tools years ago. Almost lost a finger trying to help a friend adjust his torsion bars after he added a spoiler to his Mach1 using the "Vice Grip" method. Finally sent him to the body shop and I went in to nurse a very sore hand with a "Almost" broken finger! https://secure.cougarpartscatalog.com/trunktool2.html

 

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I recently did this job. I purchased the tool mentioned above from West Coast Cougar and could not get it to work with my car (fastback body with the rear fold down seat). It may work on other body shapes and with out the fold down seat option. For me the purchase of this tool was a waste of time (and money) - it may have worked if I decided to get the grinder out and hack it to bits. There just wasn't enough room to place the tool and turn like their video shows (at least in my car).

So in the end I tried several tools such as pry bars but vice grips did the trick. When the torsion bars are installed correctly they are under reasonable tension so you need to be careful. Think about if you slip where your face (especially your eyes) are at the time. Wear good gloves too.

The catch is figuring out the correct way to install the torsion bars. When I initially attempted to install the bars the trunk would not remain open/stay up. I then noticed I could remove the torsion bars by hand - at this point I'm thinking what's all the fuss about these being dangerous, etc. I read the 71 Ford service manual, plenty of youtube videos and research on here and other sites but I struggled to figure it out exactly. The Ford service book said identify the left and right bars (there is a difference - your third photo sort of shows it) one of them was supposed to have a yellow paint mark on it but this was long gone for me. After many attempts (it seems there are a few configurations) when you install each bar you place one end of the bar at the pivot point, at the other end with the three adjustment notches using the vice grips you turn the bar thinking it terms of a circle three quarters of a turn then place it into one of the notches. For me the key was turning the bar three quarters of a circle to get the tension. Initially I was only turning the bar about a quarter to half a turn and this would not apply enough tension to keep the trunk open. The bar should be under decent pressure when inserting into a notch.

I used the vice grips to remove also just ensure the adjustment is tight and don't let go. You may (will) scratch some paint. I have a factory rear spoiler and the trunk stays open fine. There is a thicker version torsion bar that I've read others say you need for the rear spoiler. I have both - in my opinion the measurement difference is so little I cannot see how it would make a difference. I have the thinner version installed and it is working ok. I have the torsion rods in the position closest to the rear of the car. The difference in a successful installation may also be which bar gets installed first, ie. one bar goes under the other.

At the end of the day use a method that you are most comfortable with. The job does need some patience but the next time I do this it would be a five minute job as opposed to a one hour job!

Untitled.jpg

 
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Gary

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Looks as though the original tool has been replaced with a more robust one. I sure wish I'd had one of these tools years ago. Almost lost a finger trying to help a friend adjust his torsion bars after he added a spoiler to his Mach1 using the "Vice Grip" method. Finally sent him to the body shop and I went in to nurse a very sore hand with a "Almost" broken finger!  https://secure.cougarpartscatalog.com/trunktool2.html
Steve,

Thanks for posting the video that demonstrates the tool used for the Cougar torsion bars.  I've looked it over and the torsion bars for the 71 Mustang are different.  I don't think the particular tool will work on the torsion bars I posted pictures of.  I was happy to hear that your hand was only sore and not broken.  Last month I read a post about a guy who went to the hospital when the bar came lose from the vice grips.  I hope more guys post information on how to safely install trunk torsion bars. - Gary

 
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I made a tool to adjust the trunk torsion rods on my convertible. It works really well, feels locked in place and does not slip off. I have adjusted the rod up and down on the first and second notches, but not up to the third notch. That would be a lot of torque on the rod. It should work on coupes as well since the rod and trunk are setup the same way as a convertible, but I doubt it will work on a fastback.

No need to spend money on one. I used a piece of heavy gauge strap iron and drilled holes and bent it as you see in the pictures below. I think the key to it working so well was to create (drill) a open ended hook like hole on the end to keep the tool from slipping off the Torsion Bar when applying leverage. The second hole is 5/16" in diameter to keep it snug on the end of the rod and no more than 3 1/4" distance from right angle end, otherwise a metal lip where the rod wrap around will prevent the tool from hooking on to the rod.

Anyway I hope it helps....



 
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I've used a "long" tube to remove/place back that torsion bar, with a car hydraulic jack on wood blocks to support it.

I don't recall it was that challenging, just the kind of work you wish to have 4 hands.

 
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I'm intrigued.  My trunk lid don't stay open.  I'm going to take some pics and hopefully get some feedback on what's incorrect
Pictures are a big help. Do you have a Coupe/vert or fastback as the torsion rods are different. Be sure to mention if you have a spoiler and what notch your rod is currently set to.  I had a problem with trunk lid to quarter panel top alignment on the left and right sides. The trunk was being twisted slightly by the uneven torque applied by the one torsion rod. I added a second torsion rod on the other side and the trunk alignment problem was gone. If you currently have only a single rod, i would suggest installing the complimentary second rod. The left and right rods when used in pairs are different from each other. Also there was a grommet used to keep the bars from grinding and banging together where they crossed one another. I could not find one and had to make it.



 
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Its A Coupe. One bar fitted. Someone mentioned that one bar may make the deck lid be out of line. I didnt get a pic of hinges but the right one definately runs at a angle whilst the left one id straight. So may i got to fit the second bar. Heres a couple of pics showing position of the bar. The deck lid will not stay up

20170704_125013.jpg

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20170704_125102.jpg

 
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Didn't know about any such tool when I did mine, I just used a big set of Vise Grips to wind the tension on and another set to hold the other end in place. Had no problem, BUT I must admit, a proper tool is far better and safer. Very good info for future times.

Reading posts above, mine is on a fastback with a spoiler, so it's got all the tension possible on both rods to hold it up.

Geoff.

 
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Steve,

On the right hinge your torsion rod is in the upper most position which puts the least amount of tension on the trunk lid to keep it up. Most cars had the rod in the middle position on the right for tension. Try moving the rod to the middle position and see if it works.

 
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Steve,

On the right hinge your torsion rod is in the upper most position which puts the least amount of tension on the trunk lid to keep it up. Most cars had the rod in the middle position on the right for tension. Try moving the rod to the middle position and see if it works.
Thanks Jeff. Will try that ::thumb::

 
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Its A Coupe. One bar fitted. Someone mentioned that one bar may make the deck lid be out of line. I didnt get a pic of hinges but the right one definately runs at a angle whilst the left one id straight. So may i got to fit the second bar. Heres a couple of pics showing position of the bar. The deck lid will not stay up
Jeff is correct moving the bar to the middle will give it more tension, but the picture is upside down. So it is currently in the bottom position on the left side and moving it up will provide more tension. I flipped the picture right side up below...





 
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Mine is a coupe. Set up as follows with only one bar, no issues keeping trunk open and no alignment issues.....

Passenger side is in top most slot. Drivers side is in middle slot.

 
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