Shocks/ strut replacement question.

[MadMuirder]

I'm ready to lower my mustang ('17 GT with PP) but I feel I'm not informed enough to make a decision. I've done a lot of reading, originally I was sold on Steeda Sport Progressives, now I'm not sure if I want those or BMR Handling springs....

My car is a daily driver. I commute 25 miles each day each way, and have some twisty roads but nothing extreme. I wouldnt mind a rougher ride, but I dont want my (soon to be) wife to ride in my car and get pissed at every bump in the road I hit. But I do want good feel in steering/cornering.

Two real questions though.
First, is there some good resources for learning all the basics on the s550 suspension? Like I see people recommending lateral link upgrades and all sorts of things, and I want to know what each of those stock pieces do prior to replacing them - I'm an engineer and I like to learn why before I make a change.
Second, I have 30k miles on my car. If I went with some of the springs many folks have put on their car "that go well with the PP shocks/struts", should I even consider replacing my shocks and struts or no? I dont want to install new springs just to have my shocks/struts go out in 10k miles or something...so is there a way to determine life left in a shock/strut assembly ?

Sponsored

 

[Grimace427]

This is all my opinion:

• Always upgrade the dampers when installing lowering springs, both for performance and ride quality
• Besides springs and dampers, add a rear subframe isolation kit from either BMR or Steeda for the best performance improvement with minimal loss of ride quality/noise
• Additional links/arms are unnecessary for a daily driver.
• Always get an alignment when doing major suspension replacements, then approx once a year/every tire replacement after that

I couldn't tell you which brand to pick but I'd shoot a message to @bmrtech or @tjsteeda and they can certainly help you pick the right parts for you.

 

[BmacIL]

This is all my opinion:

• Always upgrade the dampers when installing lowering springs, both for performance and ride quality
• Besides springs and dampers, add a rear subframe isolation kit from either BMR or Steeda for the best performance improvement with minimal loss of ride quality/noise
• Additional links/arms are unnecessary for a daily driver.
• Always get an alignment when doing major suspension replacements, then approx once a year/every tire replacement after that

I couldn't tell you which brand to pick but I'd shoot a message to @bmrtech or @tjsteeda and they can certainly help you pick the right parts for you.

I'd agree here and also: always clock your bushings after lowering the car.
https://www.mustang6g.com/forums/th...hose-bushings-after-lowering-your-s550.44129/

There are many good options. My particular path is a bit more handling focused than many, but I still DD my car and my wife doesn't complain about the ride. With some recent changes, it honestly rides great. I'd be happy to help and share my experiences.

 

[ugstang17]

BMR has NEVER failed me. Can't say that for your other option. Kelly is ALWAYS a reply away. These guys and their products are top notch. When I brag on someone it isn't over a one and done purchase experience. It's because of repeated business with repeated quality support, service, and products.

Send him an email through their website or call them. They still take tech support phone calls.

 

[Grimace427]

I'd agree here and also: always clock your bushings after lowering the car.

This really should be something a competent alignment tech would know and take care of during the alignment. Shame it isn't more common knowledge.

 

[BmacIL]

This really should be something a competent alignment tech would know and take care of during the alignment. Shame it isn't more common knowledge.

Well not every OEM does it and it's a really stupid design on Ford's part. Their vehicle dynamics engineers have to fight with two hands behind their backs because of the bind those suspension bushings cause, even when 'clocked'. The indexing teeth (see below) on the bushings bite into the mounting faces when the bolts are torqued, and it forces the bushing rubber to twist, inducing spring rate into the suspension that it doesn't need. This is all outside of allowing a ton of deflection under load during braking or acceleration, in the case of the front tension links or rear LCA bushings.

 

[Norm Peterson]

Well not every OEM does it and it's a really stupid design on Ford's part.

Stupid when it comes to moving the car away from Ford's design ride height I'll give you.

But there are other reasons that for which it's a good if not great idea. Let's keep in mind that Ford expects these things to be installed once and generally never touched again. So from their point of view it's fine to just lock them in on the assembly line and call it done.

There's also a reason that's actually related to one of the more common complaints regarding aftermarket poly-bushed components, none of which I know of use a toothed inner sleeve. I'm speaking of the 'clunking'. This happens when the inner sleeve is not clamped with sufficient force to prevent slippage. This slippage isn't much, as it's limited by bolt to hole clearances. But when the sleeve slips from a combination of suspension movement plus some horizontal force, all those bolt to hole clearances are suddenly taken up, metal to metal with a fair amount of force. Those "teeth" are there to guarantee that no slippage - meaning clunking - can occur. Cheap and effective . . . seems to me it's the ideal regular production solution.

As to the added spring rate, I have no doubt that the suspension team takes this into account, dynamically as well as statically.


It's really on the installer of the lowering springs to reclock any bushings. Who may or may not be the same person or shop doing the alignment.


Norm

 

[BmacIL]

Stupid when it comes to moving the car away from Ford's design ride height I'll give you.

But there are other reasons that for which it's a good if not great idea. Let's keep in mind that Ford expects these things to be installed once and generally never touched again. So from their point of view it's fine to just lock them in on the assembly line and call it done.

There's also a reason that's actually related to one of the more common complaints regarding aftermarket poly-bushed components, none of which I know of use a toothed inner sleeve. I'm speaking of the 'clunking'. This happens when the inner sleeve is not clamped with sufficient force to prevent slippage. This slippage isn't much, as it's limited by bolt to hole clearances. But when the sleeve slips from a combination of suspension movement plus some horizontal force, all those bolt to hole clearances are suddenly taken up, metal to metal with a fair amount of force. Those "teeth" are there to guarantee that no slippage - meaning clunking - can occur. Cheap and effective . . . seems to me it's the ideal regular production solution.

As to the added spring rate, I have no doubt that the suspension team takes this into account, dynamically as well as statically.


It's really on the installer of the lowering springs to reclock any bushings. Who may or may not be the same person or shop doing the alignment.


Norm

Yes it's for manufacturing primarily. A way to prevent the clunking would be to have a crush tube/sleeve inside the over molded tube, one which has nearly a press fit for tolerances. Enough to allow for rotation, won't bind up the arm when torqued. This would pretty much guarantee no clunking.

This is how bad the bind is (borrowed from Vorshlag blog). It may be taken into account, but I can vouch from experience that removing the bind actually is a noticeable and significant improvement to ride.

 

[NightmareMoon]

Two real questions though.
First, is there some good resources for learning all the basics on the s550 suspension? Like I see people recommending lateral link upgrades and all sorts of things, and I want to know what each of those stock pieces do prior to replacing them - I'm an engineer and I like to learn why before I make a change.
Second, I have 30k miles on my car. If I went with some of the springs many folks have put on their car "that go well with the PP shocks/struts", should I even consider replacing my shocks and struts or no? I dont want to install new springs just to have my shocks/struts go out in 10k miles or something...so is there a way to determine life left in a shock/strut assembly ?

IDK any good resources that list the roles of each part. With the exception of the springs, shocks, and swaybars, most parts are just connections between joints and don't do anything functionally interesting except to implement the required geometry. There is a lot of rubber in the stock suspension, but IMHO that's not so terrible for a daily driver unless you're specifically trying to eliminate something that's bothering you, a handling characteristic, or wheel hop or something. Honestly I wouldn't touch anything other than springs and shocks at first. You can always go add subframe bracing later, that stuff is easy to install after the fact and it won't affect your alignment, so its easy to put off for a while.

The main difference between the Steeda progressive springs and the BMR handling springs is the Steedas seem to be designed for that 1" lowering look and to ride well over small bumps and smoother roads (daily driver stuff). The BMR springs seem to be more practical about getting performance without going overly stiff. The BMR springs keep the rear a bit higher to keep you off the bump stops and they go for a more noticeable increase in spring rate in the front, which really benefits handling. IF well dampened with suitable shocks the ride should be fine with either option. With the BMR handling springs, shocks will be a must. Steeda wants to sell lots of Progressives to casual drivers, so they advertise they're ok with the stock PP shocks, but they're probably better with other shocks.

New (slightly heavier duty) shocks alone can transform the car's handling potential without much sacrifice in ride quality. Shocks tend to fade over time progressively, slowly loosing their damping as they age to ~60k-100k miles. If yours are 30k old, they're likely already not as firm as they were when you bought the car, and the PP shocks are arguably a bit soft for the PP springs even when new, let alone higher rate lowering springs. Considering there is not a lot of extra labor to do both springs and shocks at the same time I'd recommend going ahead and replacing your shocks at the same time as you do the springs. Aside from the money, you won't regret it.

For shocks, people seem to like the Ford Track shocks for non-adjustables (they're really not as hard-core as they sound, more of a sport shock than a true track shock anyway). Personally I like having single (rebound) adjustables, but I think they cost a little bit more than the Ford track shocks. At least with the adjustables, you can fine tune for your ride comfort preferences or if you like to fiddle with things.

Clocking the bushings (as mentioned) is a must BEFORE you get the car aligned for the long term. The car won't even lower all the way with the rubber bushings bound at the stock ride height.

 

[MadMuirder]

I'd agree here and also: always clock your bushings after lowering the car.
https://www.mustang6g.com/forums/th...hose-bushings-after-lowering-your-s550.44129/

There are many good options. My particular path is a bit more handling focused than many, but I still DD my car and my wife doesn't complain about the ride. With some recent changes, it honestly rides great. I'd be happy to help and share my experiences.

Thanks! I've been lurking for a while, and seen a lot of your replies here on 6g. I'll be sure to pick your brain soon, tonight is the Mrs. Birthday and tomorrow is a mini road trip!

 

[SteedaTech]

I'm ready to lower my mustang ('17 GT with PP) but I feel I'm not informed enough to make a decision. I've done a lot of reading, originally I was sold on Steeda Sport Progressives, now I'm not sure if I want those or BMR Handling springs....

My car is a daily driver. I commute 25 miles each day each way, and have some twisty roads but nothing extreme. I wouldnt mind a rougher ride, but I dont want my (soon to be) wife to ride in my car and get pissed at every bump in the road I hit. But I do want good feel in steering/cornering.

Two real questions though.
First, is there some good resources for learning all the basics on the s550 suspension? Like I see people recommending lateral link upgrades and all sorts of things, and I want to know what each of those stock pieces do prior to replacing them - I'm an engineer and I like to learn why before I make a change.
Second, I have 30k miles on my car. If I went with some of the springs many folks have put on their car "that go well with the PP shocks/struts", should I even consider replacing my shocks and struts or no? I dont want to install new springs just to have my shocks/struts go out in 10k miles or something...so is there a way to determine life left in a shock/strut assembly ?

I'm ready to lower my mustang ('17 GT with PP) but I feel I'm not informed enough to make a decision. I've done a lot of reading, originally I was sold on Steeda Sport Progressives, now I'm not sure if I want those or BMR Handling springs....

My car is a daily driver. I commute 25 miles each day each way, and have some twisty roads but nothing extreme. I wouldnt mind a rougher ride, but I dont want my (soon to be) wife to ride in my car and get pissed at every bump in the road I hit. But I do want good feel in steering/cornering.

Two real questions though.
First, is there some good resources for learning all the basics on the s550 suspension? Like I see people recommending lateral link upgrades and all sorts of things, and I want to know what each of those stock pieces do prior to replacing them - I'm an engineer and I like to learn why before I make a change.
Second, I have 30k miles on my car. If I went with some of the springs many folks have put on their car "that go well with the PP shocks/struts", should I even consider replacing my shocks and struts or no? I dont want to install new springs just to have my shocks/struts go out in 10k miles or something...so is there a way to determine life left in a shock/strut assembly ?

I'm ready to lower my mustang ('17 GT with PP) but I feel I'm not informed enough to make a decision. I've done a lot of reading, originally I was sold on Steeda Sport Progressives, now I'm not sure if I want those or BMR Handling springs....

My car is a daily driver. I commute 25 miles each day each way, and have some twisty roads but nothing extreme. I wouldnt mind a rougher ride, but I dont want my (soon to be) wife to ride in my car and get pissed at every bump in the road I hit. But I do want good feel in steering/cornering.

Two real questions though.
First, is there some good resources for learning all the basics on the s550 suspension? Like I see people recommending lateral link upgrades and all sorts of things, and I want to know what each of those stock pieces do prior to replacing them - I'm an engineer and I like to learn why before I make a change.
Second, I have 30k miles on my car. If I went with some of the springs many folks have put on their car "that go well with the PP shocks/struts", should I even consider replacing my shocks and struts or no? I dont want to install new springs just to have my shocks/struts go out in 10k miles or something...so is there a way to determine life left in a shock/strut assembly ?

I would recommend reaching out to the different vendors directly on this forum and get their opinion as well. Furthermore, Check out Steeda's blog for their accomplishments at https://www.steedablog.com/2018/10/

[email protected] or [email protected] would be a good start to get your questions answered.

All the best,
Steeda.Tech

 

[Coyote Red]

This is a good thread with much input from several knowledgeable members. I am contemplating shocks currently as I lowered my pony 1.5" fr 1.1" rear. Much like the Eibach pro kit. I am 5,000 miles into the oem shocks & struts and the ride is sporty but a little stiff, lots of travel. At 50,600 miles I need to do shocks when? You should research further what the cars goals/uses are and then with all these guys help & input you can make your decision.I may continue the OEM's until June.

 

[Norm Peterson]

Yes it's for manufacturing primarily. A way to prevent the clunking would be to have a crush tube/sleeve inside the over molded tube, one which has nearly a press fit for tolerances. Enough to allow for rotation, won't bind up the arm when torqued. This would pretty much guarantee no clunking.

Tube inside a tube on the ID of the rubber part? I wonder how much clearance it takes for rod ends to start getting a bit rattley . . .

This is how bad the bind is (borrowed from Vorshlag blog). It may be taken into account, but I can vouch from experience that removing the bind actually is a noticeable and significant improvement to ride.

Seen that picture, and it's just crazy. Hope those bushings are fairly strongly progressive so you're not adding 50+ lb/in wheel rate immediately away from static ride height. I'll have to pay attention to the variation in tire to fender gap next time I'm near an unlowered S550 in traffic that's moving along at a decent speed.


Norm

 

[BmacIL]

Tube inside a tube on the ID of the rubber part? I wonder how much clearance it takes for rod ends to start getting a bit rattley

It's on the ID of the rubber, but it's bonded to it, I believe via overmold. I'm not exactly sure on the clearance needed, but the nice (tight clearances) rod ends/sphericals don't rattle much, if any. I think there's a way to engineer it, they just chose the cheap route, despite being worse. My estimate is <$5 per car to change that to something like what I proposed. Unfortunately Flat Rock would complain and they'd cave.

Sponsored