Leaf spring replace: DIY or shop?

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Aus73Mach1

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1973 Mach 1 Sports Roof.
Q code. 351-4V
C6 Auto, 3.25 Rear Axle, AC, Power steering.
Both front eye bolts on mine were frozen solid. Even a gas torch didn't move them and not much room for a big hammer. Sitting on the shelf in the shed was this small bottle jack I made years ago during a trade course. I was never sure what it would ever be used for but with a strip of steel against the back of the rocker panel it fitted nicely against the eye bolt. After plenty of penetrating oil, the jack pushed the bolts through. Still took a lot or force on the adjusting nut to break the bolts free. So my motto has always been, never throw anything out, it may come in handy one day.

20201022_084342.jpg

 

detritusmaximus

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1970 Sportsroof #2 almost as long
1971 Sportsroof M-code #3 needs money
2008 GT #4 where the money went
Hand tools, air tools. BFH and drift, Floor jack and stands, can of Aero Kroil. Job can be tedious but not really a hard job.
KROIL! Best stuff on earth...

A word about working with jack stands...when you raise the car and take the wheels off, slide the wheels under the car ahead of the jack stands. If anything happens, the car lands on the tires, not you.

 
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detritusmaximus

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It could well turn out to be a PITA, but everyone is assuming the Eye bolts will be rusted in. Perhaps jscott can take a look at them and get back to us. It might not be too bad to do.............. or not!
took a wrench to one side and a socket to the inside and yanked and yanked and so on..........it took some muscle both both eye bolts turn and outside nuts were removed, then re-installed as I am not ready to swap at the leaf springs yet.  Same with the shackle nuts, they seem to be moving as well.   I assume pushing out  the eye bolt once the nut is off will be not that hard as it is turning.

 

71 gbvert

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Bought it in 1986. Base model convertible with a 302 3spd.
Watching this as the rear springs are next on my list.  No ceramic hips but I can relate having spinal fusion done....  Good luck and keep us updated!

 
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Now looking at the springs, as others have mentioned Eaton springs are the best and I guess the price reflects that.  Looking at stock +1" my springs would be $665 to my door for everything.     I realize most speak from experience but I have to ask, are they that much better then the kits offered by either KY mustang at $230 for all or CJ at the same price.  Are theirs Chinese springs??    I think I answered own question, buy the quality always but I have to ask in case some have used the other kits, can't hurt to ask.

 
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Ditto on the leaf springs for me in the spring 2021. Put car away for winter storage today.  I had guys at Eaton spring quote me non-performance set ,+1 inch   and but never followed through.  I'll also be watching this post.   

 

goodnigh

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Got mine from Summit Racing, five leaf.  Easy enough to do yourself

and they raised the rear about one and a half inches.  The car looks

level now.  

Here are the springs we ordered from Summit Racing

https://www.summitracing.com/parts/sdk-c5zz-5560-hd

mike

 
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I answered this in your other post, but to recap. I bought Scott Drake(?) Grab-a-Track 4.5 leaf and they were way too high for my liking. I had them de-arched, but unfortunately the worker at the shop over did it and took too much out. After that, the springs started bending backwards, so likely a combination of over de-arching them and maybe crappy steel. That's why I went back to Eaton. 

Eaton can custom make just about anything you want if you want to wait and pay for it.

You get what you pay for.

If you want an alternative, Rock  Auto sell Dayton springs and have a performance  spring at 153 lb spring rate. I have no idea about their quality, but they are a huge spring manufacturer, mainly truck springs, but they also make for other brands. Do they make for S/D, I could not find that out, so who knows.

 
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I have the Meier springs and they are awesome. These are 4.5 leaves and rated at 160. Great comfortable ride and zero wheel hop. I didnt know the Eatons were that expensive. At that price for Eatons, the Meiers are competitive. It is true that you get what you pay for.

Edit: ride height ended 1/2" lower than what i had. I ended up adding a 1" longer shackle to even the ride height. This winter i will upgrade to Meiers MOD1 front suspension. I then can lower the front to match the rear without the longer shackle. 

 
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so while I am leaning to get what seems to be considered the best (Eaton) I had to ask KY mustang this question as I want to check all the options.  KY Mustang is  one of my main go to suppliers, from my dealings with them I have nothing but good things to say.  Their response is below in red.

https://www.kentuckymustang.com/Leaf-Spring-Kit-1964-1-2-1973-p/5453.htm

I will be replacing the leaf springs on my 1972 Fastback and have to ask this.  Your package at $229 is a great deal but what about the quality?  On the 7173 forum many recommend Eaton springs which will cost $665 for their package (delivered). That is a Big difference.  I assume you have sold many of these, and it so what has been the response?   Any thoughts or comments would be appreciated. 

Hello,

Thank you for contacting us!


I have sold hundreds of these same springs as they fit 67-73 and have no issues whatsoever. We put these on our own cars as well (I put the exact same ones on my 67 Fastback plus we have a 69 Mach 1 that we put them on). They are very nice leaf springs and we have good feedback from customers about them as well.

Please contact us if you need anything else.
Best regards,

Jacob
Kentucky Mustang


 
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so while I am leaning to get what seems to be considered the best (Eaton) I had to ask KY mustang this question as I want to check all the options.  KY Mustang is  one of my main go to suppliers, from my dealings with them I have nothing but good things to say.  Their response is below in red.

https://www.kentuckymustang.com/Leaf-Spring-Kit-1964-1-2-1973-p/5453.htm

I will be replacing the leaf springs on my 1972 Fastback and have to ask this.  Your package at $229 is a great deal but what about the quality?  On the 7173 forum many recommend Eaton springs which will cost $665 for their package (delivered). That is a Big difference.  I assume you have sold many of these, and it so what has been the response?   Any thoughts or comments would be appreciated. 

Hello,

Thank you for contacting us!


I have sold hundreds of these same springs as they fit 67-73 and have no issues whatsoever. We put these on our own cars as well (I put the exact same ones on my 67 Fastback plus we have a 69 Mach 1 that we put them on). They are very nice leaf springs and we have good feedback from customers about them as well.

Please contact us if you need anything else.
Best regards,

Jacob
Kentucky Mustang
Well, at the end of the day, it's your money to spend as you see fit. All I'm doing is passing on my bad experience buying cheap springs and that's my opinion.

I would however, ask who make the springs they sell. Selling hundreds doesn't necessarily mean they are good. If they're made in the US by a known company like Dayton, you're probably ok. Funny thing is, I was quoted far more for Dayton springs at my local dealer, in Canadian dollars, than I was for Eaton, also supplied by a Canadian dealer.

Buy what you feel is best for you at this time. I hope buying cheaper doesn't come back to bite you as it did me.

 
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I am copying this from Mike Meier's page for leaf springs. I find this very persuasive from a person that really knows these cars and has raced Mustangs for years. At the end of the day it will also depends on what your driving intentions are. If you are into spirited driving, autocross and/or racing, it is different than just a nice drive around the city. The latter does not justify spending that much more for suspension, but the former it does.

https://mikemaierinc.com/products/64-73-mustang/rear-suspension/64-73-mustang-mod-leaf-springs/


These aren’t your typical leaf springs


Mustang leaf springs tend to get a bum rap, but that’s only because the typical designs out there are circa 1975. We’ve seen people buy a set, be disappointed in the results, then blame it on their 50 year old car. But that’s simply not true. When we bring modern technology and design to leaf springs, we can create a rear suspension that performs, installs simply, and keeps down the weight.

The most common complaint associated with leaf springs is wheel hop, the chatter you feel when accelerating. Poor leaf spring design allow the front half of the leaf to deform/deflect causing axle wrap up which snaps back and induces wheel hop.

That’s why our springs have been designed with an extra two leaves toward the front, with a beefy wrap to add additional strength. We have guys with 900+ hp applications running these springs and they’re still not experiencing wheel hop.

The other big complaint we hear is ride quality. More often than not, people end up selecting a solid or urethane bushing for the spring saddle which we’ve found to be problematic for two reasons. First, it makes the ride extremely harsh, and second, it actually binds up the rear and prevents the suspension from working well during cornering.

For a stock setup, leafs have two jobs: they move up and down to absorb shocks, but they also move side to side, working to keep the axle centered. During cornering, the leaf is moving both up and down, and side to side, absorbing bumps through the turn without knocking the car off course. Replacing the bushing with a solid material prevents the spring from moving side to side, increasing bind and ultimately resulting in unpredictable feel. That’s why we actually prefer the stock rubber for the leaf shackles as it allows the suspension to do it’s job.

We do recommend and include a urethane bushing for the leaf eyelets, as this helps to keep the car under control during acceleration and braking far better than the standard rubber.

We’ve also intentionally recurved the spring to bring the ride height to what we consider to be the best, about 8″ from the pinch weld to the ground. This slightly lowered setup puts the suspension in the best place for overall geometry.

We’d also recommend upgrading to our panhard setup to help further control the side-to-side movement of the rear end.

This setup is a simple, budget-friendly option that is highly effective both on the street and track. We’ve seen dramatic improvements in feel, responsiveness, and ride quality by simply replacing stock or other aftermarket components with this setup.

 
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I agree and I am sure I will end up with Eaton but always want to check all options.  At that price I am sure KY kit is "imported".
doing due diligence is the key. There's a lot of time and work involved to get our cars to where WE want them for our own satisfaction, buy what makes you happy when it's done..

 
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