new shocks advice

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Vinnie

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Hey folks,

I think I need new shocks, at least at the front, because these rubber things have started cracking:

IMG_5867.JPG


I'd like to ask a few questions about replacing the shocks:

1) What's the procedure? Does the car need to be lifted or can it stay on the ground?

2) I can replace with standard shocks, but are there certain shocks that improve handling that I should be aware of?

3) Will new shocks change the stance of my car? Currently this is how it sits:

IMG_3355.JPG


Thanks!

Vincent.

 

Bill73Ragtop

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former owner (25 yrs) of 1973 Convertible, 351c, A/C, RA
You could start with just replacing the shock tower bushings. Some of the aftermarket bushings are made with some pretty cheap material and can break down in a couple hundred miles. Replacing with poly generally takes care of that problem for a long time. https://www.summitracing.com/parts/ens-9-8101g/overview/

Changing the shocks typically involves jacking the front up and supporting the vehicle since removing the front wheels really helps gain access to the nuts and bolts inside the coil at the bottom of the shock at the coil perch.

I'm sure others will chime in on the recommendation of what to replace original stock shocks with. Be careful with getting shocks that are too high performance since the ride can get pretty stiff and harsh. KYB and Koni make some decent replacements at reasonable cost.

 

luxstang

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I've used KYB for gears and they are great. They improve handling but don't reduce comfort.

Plus they're pretty cheap and offer great value for money.

You need to jack the car up and remove the wheels to gain access to the shocks at the bottom.

You don't need to compress the springs, it's a simple task.

DO NOT remove the band that holds the new shocks compressed too early or you'll have a hard time putting the shocks in as they'll expand.

The stance and ride height are determined by the coil springs, not by the shocks so nothing's gonna change.

 

goodnigh

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Got KYB up front and Koni adjustable in the back

with new 5 leaf springs. Stiff ride and great handling.

Car has factory competition suspension package.

As Luxstang mentioned, KYB's are relatively inexpensive,

Koni's are not.

mike

 

red351

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I been running KYB's on both cars for years. They been good for what they cost. The only problem is I bought the one's recommended and ended up with the shorter (when fully extended) front shock. they pull the top bushing and splits it when the car on the lift. The longer shock leaves less spring down pressure. I had cut some donut out of flat belt material and use them on top. Problem fixed

 

Fabrice

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Koni front and back. Went from original tired ones to these years ago when these were not sold for gold prices.

I recall car felt totally different, much safer. Comfort is great.

For the upper bushings on front, the summit Polyurethane should be fine. I make my own from polyurethane plates for years, as its easy

and cheap , but for 4 dollars its no brainer, and much better than rubber ones.

[Will new shocks change the stance of my car? ]

Not really, springs will. Changed mine as well with stronger versions with original size. Car was too high on front for my taste, so cut one revolution

and got what I wanted.

 
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A little refresher on why the shock upper bushings split.

Remember the special tool that you use when you lift the front of the car? Depending on the shock it can run out of travel before the control arm gets to it's lowest position. This puts all the force of the spring on the bushing and causes it to split. It also puts a shear force on the rubber bushing in the radius rods up front and can cause them to split also. Anytime a Mustang is lifted in the front you should use the special tool to stop the travel of the upper control arm. It was a standard Ford tool and lots of people make their own. You can also cut a piece of wood and put between the frame and control arm if you do not want to build steel.

Do a search for the thread on the subject. I tried to do a screen print of the tool but it went crazy when I put in post. I tried a word document this time see if it works.

David

special_Tool_Mustang.docx

 

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Vinnie

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A little refresher on why the shock upper bushings split.

Remember the special tool that you use when you lift the front of the car? Depending on the shock it can run out of travel before the control arm gets to it's lowest position. This puts all the force of the spring on the bushing and causes it to split. It also puts a shear force on the rubber bushing in the radius rods up front and can cause them to split also. Anytime a Mustang is lifted in the front you should use the special tool to stop the travel of the upper control arm. It was a standard Ford tool and lots of people make their own. You can also cut a piece of wood and put between the frame and control arm if you do not want to build steel.

Do a search for the thread on the subject. I tried to do a screen print of the tool but it went crazy when I put in post. I tried a word document this time see if it works.

David

Yeah I’ve seen the tool, it’s also mentioned in the book from Haynes. Maybe I can make my own from some scrap metal.

 

luxstang

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About that tool...:

One thing I always wodered is how do you intall the tool prior to lifting the car when you need to lift it before you can access the area where you put the tool?!?

I never had any bushing crack on me btw, no matter how I lifted the car. It does seem others have though....

 

goodnigh

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Koni front and back. Went from original tired ones to these years ago when these were not sold for gold prices.

I recall car felt totally different, much safer. Comfort  is great.

For the upper bushings on front, the summit Polyurethane should be fine. I make my own from polyurethane plates for years, as its easy

and cheap , but for 4 dollars its no brainer, and much better than rubber ones.

[Will new shocks change the stance of my car? ]

Not really, springs will. Changed mine as well with stronger versions with original size. Car was too high on front for my taste, so cut one revolution

and got what I wanted.
Tried to get Koni's for my front shocks but did not sell them

in the States, only rear.

mike

 

Bentworker

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I'm partial to Bilstein shocks, no particular reason.

If you decide to swap your upper shock mount to the pre 68-70 style you will have a lot more shock options (Bilstein makes some).  The good thing about the swap is that it is just bolt on, and can always be swapped back later if guilt overcomes you for straying from the original design.

This is the early pre 68-70 style shock mount  / tower cap with a cheapie shock on it showing extended length (roughly 12 5/8" mounting surface to mounting surface.)  



This is a 71-73 style shock mount / tower cap with an ancient shock showing its extended length of approximately 12 1/2" mounting surface to mounting surface.



I found that the extended and collapsed lengths between the two designs were within a quarter inch.  
 
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About that tool...:

One thing I always wodered is how do you intall the tool prior to lifting the car when you need to lift it before you can access the area where you put the tool?!?

I never had any bushing crack on me btw, no matter how I lifted the car. It does seem others have though....
I have to make road trip tomorrow to pick up an engine but will take some pictures when I get back on Sunday. You jack up under the lower arm and take the wheel off or just turn the wheel and block the suspension. I will show you in pictures that when you lift the car without something to stop the travel the rubber get mashed to a couple of millimeters thick. If you block it looks normal. It is what kills the bushings lifting without blocking the suspension.

David

 

Fabrice

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@goodnigh

[Tried to get Koni's for my front shocks but did not sell them in the States, only rear.]

Yeah well, it's way around for once! :) I have to order everything in the states.

@David

[the rubber get mashed to a couple of millimeters thick]

Not having the luxury of a lift and not even knowing there was a tool for this, I've crushed and ruined a few pairs in the garage over the years. When newly replaced, I did unscrew to reduce the pulling pressure but always forgot do it after a while. Tired of it I made my own polyurethane copies. Never had to change them again and pretty sure the car will never need a new pair ever.

 
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Ok guys I did a little test yesterday and took some pictures. I had my 73 vert on the two post lift when taking the power steering pump off to put a seal kit in. I have a series of pictures.

#1 is picture of the upper shock mount to show the rubber while sitting on the tires.

#2 is a picture showing the control arms. I did some measuring and it is as simple as taking a piece of what we call 2X4 and place on top of the frame rail so that as you lift the car the upper control arm hits the block of wood and stops the travel short of squeezing the shock mount bushing.

For our Metric guys the bock of wood is 1 5/8" thick or 41.3 mm.

#3 is a picture with the wood block in place.

#4 is picture of the rubber with the block in place.

#5 is a picture of the opposite side with no block in place and the rubber is crushed to nothing.

The tool does not have to be the elaborate one that Ford had. I would use a piece of Oak wood if you have it.

The rubber bushing on the shock is to isolate it from the metal. The shock has very little pressure compared to the coil suspension spring. You can compress the shock with your hands but you will not budge one of the front coil springs with thousands of pounds of force.

It is easy to reach in behind the tire slip the block of wood in on top of the frame under the front of the upper control arm and you will never split a shock bushing again.

I have a NOS set of Ford front shocks that I need to pull out and check the extended length on so I can give that info to compare to aftermarket shocks. Have to find them first, lol.

David









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goodnigh

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@goodnigh

[Tried to get Koni's for my front shocks but did not sell them in the States, only rear.]

Yeah well, it's way around for once! :)  I have to order everything in the states.

I did not know that Koni's were invented in Nederlanden!

Well Done.

mike

@David

[the rubber get mashed to a couple of millimeters thick]

Not having the luxury of a lift and not even knowing there was a tool for this, I've crushed and ruined a few pairs in the garage over the years. When newly replaced, I did unscrew to reduce the pulling pressure but always forgot do it after a while. Tired of it I made my own polyurethane copies. Never had to change them again and pretty sure the car will never need a new pair ever.
 

MustangChris

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Some friends had Koni shocks on their rides and claimed they were the best. I purchased a set of Edelbrock Performer shocks for my 73 Mustang Mach 1 around 20 years ago. The car handled and rode like a dream with them. Not sure if they still make them. I highly recommend them.

 
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Vinnie, If you take a look at the "Possible Related Threads" below, look at Help! New KYB shocks Continued. post and the others listed there, you might find that helpful. I could not find my pictures attached, but I took several to help out a member with a similar issue as you. This seems to be very common, but if you read what I had found from MY experience sorting this out, it might help you also. There was some very good input from several members at that time.

If you are unable to open those post with the pictures, I can repost them. No time to do it now.

Geoff.

There is also a post "Top shock bushings" from Dec 2016. Use the search tool under "More" top right.

I remember posting pictures in one or all of these, but they don't appear to be there now. Can't figure that one out!

EDIT: Sorry Vinnie, I addressed this to Mustang Chris by mistake. Still can't find the photos I attached before. I did find them in my files, so I could repost them.

Geoff.

 
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Ok guys I did a little test yesterday and took some pictures. I had my 73 vert on the two post lift when taking the power steering pump off to put a seal kit in. I have a series of pictures.

#1 is picture of the upper shock mount to show the rubber while sitting on the tires.

David

 David, I see that in this picture, the shocks are moving around, leaving a mark. I had this issue as well and is the reason I added a thick 3/8" washer between the rubber and cap top and bottom. I found that with the nuts tightened all the way, there was not enough pressure on the rubbers to hold them in place. Since I did this, no more movement or issues.

Geoff.

 
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