FYI FORD MustangSteve's Ford Mustang Forum / New Rear Leaf Springs Installed

**Posted by BobE** 8/14/2024 7:35 AM

FYI
I just replaced my original rear leaf springs with new springs from Detroit Speed, 4.5 leaf, 1.5” drop.
Rear ride height changed from 13.5” to 14”; center of wheel hub to fender lip.
Ride quality has improved, glad I made the change (that I should have done long ago!)

**Posted by BILLY WALTON from GEORGIA** 8/14/2024 8:34 AM

How much were they? I need to measure mine I feel like I lowered mine too much.

**Posted by Nos681** 8/14/2024 1:44 PM

Did you take before and after pictures Bob?

**Posted by RTM** 8/14/2024 2:58 PM

That’s one thing I’ll always spend good money on is leaf springs. I’ve found that different brands can say they are 5 leafs but are far from being the same when it comes to the ride height and quality.

**Posted by BobE** 8/15/2024 8:11 AM

Billy:
Total Cost: $577
Spring Price: $479
Shipping: $53 (78lbs)
Tax: $44

Dan - I did not take any new pictures as the half-inch isn't really noticeable. This is a an older picture where the height is 13.5". I believe I can reduce that height to about 12.5 -13". I'll give these springs some time to settle before I do anything.

**Posted by Nos681** 8/15/2024 9:18 AM

Looks great Bob.
Should last another 50 years.

**Posted by Steve69** 8/15/2024 11:09 AM

Ill have to check out Detroit Springs. Not real happy with my ride quality.

**Posted by RTM** 8/15/2024 11:42 AM

The last set of leafs I bought never settled. I bought them from Mustang Plus many years ago. Sold that car many years ago. Lol

**Posted by Nos681** 8/15/2024 6:52 PM

What wheels and tires do you have Bob?

**Posted by BobE** 8/16/2024 8:12 AM

Nos681 wrote:
What wheels and tires do you have Bob?

American Racing Torq-Thrust, 15x7, 3.75" BS, BF Goodrich, 225/60-15s. The R&C R&P front suspension recommends 4 to 4.25" BS. I don't have a problem, but I did roll the fenders a bit, and have no interfrence.

**Posted by Nos681** 8/16/2024 7:14 PM

Thanks Bob, great information for future use.

RTM wrote:
The last set of leafs I bought never settled. I bought them from Mustang Plus many years ago. Sold that car many years ago. Lol

The 5 leaf mid-eye springs from Mustangs Plus (early 90’s) actually raised the rear of the ‘65.
Never worried about it “settling down” at all.

Still running them too.

**Posted by lowercasesteve** 8/17/2024 3:37 PM

Nos681 wrote:
Thanks Bob, great information for future use.

RTM wrote:
The last set of leafs I bought never settled. I bought them from Mustang Plus many years ago. Sold that car many years ago. Lol

The 5 leaf mid-eye springs from Mustangs Plus (early 90’s) actually raised the rear of the ‘65.
Never worried about it “settling down” at all.

Still running them too.

I have 4-leaf rears with reverse eyes. They took the car down about 1.5". Just as advertised. I got them from Mustangs Plus. Go figure.

I miss them as they were only an hour from me. I got great service from knowledgeable techs.

**Posted by BobE** 8/19/2024 3:35 PM

Finally able to upload to ImgBB.
These are 'after' the new rear springs were installed.

**Posted by lowercasesteve** 8/19/2024 4:08 PM

That looks perfect to me. Both wheels are centered on the wheel wells.

Good job. Getting that right can be upsetting.

**Posted by BobE** 8/20/2024 6:00 AM

Funny thing ... a couple of years ago, I wanted to lower the rear a bit, so I installed 1" lowering blocks. The result was no change in height, that's when it became chrystal clear that the rear springs were shot.

**Posted by MS** 8/23/2024 11:58 AM

BobE wrote:
Funny thing ... a couple of years ago, I wanted to lower the rear a bit, so I installed 1" lowering blocks. The result was no change in height, that's when it became chrystal clear that the rear springs were shot.

That seems physically impossible !

**Posted by Steve69** 8/26/2024 7:21 AM

lowercasesteve wrote:
Nos681 wrote:
Thanks Bob, great information for future use.

RTM wrote:
The last set of leafs I bought never settled. I bought them from Mustang Plus many years ago. Sold that car many years ago. Lol

The 5 leaf mid-eye springs from Mustangs Plus (early 90’s) actually raised the rear of the ‘65.
Never worried about it “settling down” at all.

Still running them too.
I have 4-leaf rears with reverse eyes. They took the car down about 1.5". Just as advertised. I got them from Mustangs Plus. Go figure.

I miss them as they were only an hour from me. I got great service from knowledgeable techs.

I have the same set of leaf springs. What shocks are you using? Mine seems really rough riding with the Bilstein shocks from street or track.

**Posted by lowercasesteve** 8/26/2024 12:11 PM

Steve69 wrote:
lowercasesteve wrote:
Nos681 wrote:
Thanks Bob, great information for future use.

The 5 leaf mid-eye springs from Mustangs Plus (early 90’s) actually raised the rear of the ‘65.
Never worried about it “settling down” at all.

It's been a while, but I have GR3's. Can't remember the maker anymore. They are not my favorites. I still prefer the old 67-68 Big Block shocks, but they are not made any more.

Still running them too.
I have 4-leaf rears with reverse eyes. They took the car down about 1.5". Just as advertised. I got them from Mustangs Plus. Go figure.

I miss them as they were only an hour from me. I got great service from knowledgeable techs.

I have the same set of leaf springs. What shocks are you using? Mine seems really rough riding with the Bilstein shocks from street or track.

Mine are GR3's - can't remember the maker. My memory sucks these days.

I still prefer the oritginal GT shocks, but they are no longer made.

Last edited by lowercasesteve (8/26/2024 12:13 PM)

**Posted by BobE** 8/27/2024 7:37 AM

Steve69 - I have KYB shocks. The ride is rough (especially compared to modern cars), but I'm not sure if it is any different from when these cars were new.

**Posted by Steve69** 8/28/2024 9:20 AM

BobE wrote:
Steve69 - I have KYB shocks. The ride is rough (especially compared to modern cars), but I'm not sure if it is any different from when these cars were new.

Hey BobE, I had those shocks many years ago and like you said they road rough. I changed them to Bilsteins and it was a little better. I hate to say it but when I had the cheap Monroe Matics back in the day that was the best my car road...LOL I might have to go back to them.

Last edited by Steve69 (8/28/2024 9:21 AM)

**Posted by kardad** 8/28/2024 12:17 PM

This almost comical as I just received my Summit order today with a set of Monroe-Matics to replace the KYB’s on the car. I realized that after all of the high dollar shocks I’ve tried that I was happier with a base gas shock like the old Monroe’s

**Posted by Rudi** 8/28/2024 1:44 PM

I originally had old Monroematics and changed to cheapo KYB and am more than pleased with them.
Funny over at VMF you almost get castrated if you don’t get Koni or Bilstein.

**Posted by Nos681** 8/28/2024 10:36 PM

Can y’all be a little more specific about which model KYB’s.

Kinda like “Coke”, “pop”, or “Crescent wrench.”

Even “Bilstein” and “Koni” have different models.

I had the KYB “Gas-a-Just” at all corners for over 25 years.

In 2020, swapped fronts over to ViKing double adjustable coil overs.

Rear still has KYB’s. (I can do that since I mentioned the model already. 😜)

Show up in a Kia or shopping cart, driving a Mustang is not a requirement…although it would be cool 😁.

My ‘65 is very similar to what it looked like 30 years ago…dents, scratches, Earl Scheib paint job, and Bondo…ok maybe some Bondo is missing.

You will have fun and meet some really great folks…big family of friends.

**Posted by BobE** 8/29/2024 1:58 PM

MS wrote:
BobE wrote:
Funny thing ... a couple of years ago, I wanted to lower the rear a bit, so I installed 1" lowering blocks. The result was no change in height, that's when it became chrystal clear that the rear springs were shot.
That seems physically impossible !

I missed this post. Yes, I agree, I can't explain it, but the tape measure doesn't lie! (I keep data like this)

**Posted by BobE** 8/29/2024 2:03 PM

Nos681 wrote:
Can y’all be a little more specific about which model KYB’s.

Kinda like “Coke”, “pop”, or “Crescent wrench.”

Even “Bilstein” and “Koni” have different models.

I had the KYB “Gas-a-Just” at all corners for over 25 years.

In 2020, swapped fronts over to ViKing double adjustable coil overs.

Rear still has KYB’s. (I can do that since I mentioned the model already. 😜)

Show up in a Kia or shopping cart, driving a Mustang is not a requirement…although it would be cool 😁.

My ‘65 is very similar to what it looked like 30 years ago…dents, scratches, Earl Scheib paint job, and Bondo…ok maybe some Bondo is missing.

You will have fun and meet some really great folks…big family of friends.

Mine are KYB 'Gas-a-Just" models, and yes they were bought a long time ago, but the car has only been on the road since 2008. With changing the rear springs, I can say the shocks are in good shape.