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Immediately
07-17-2017, 12:28 AM
I'm a new poster to the forum, so I thought I would start out by providing my impressions of a mod that many may be interested in, but few (to my knowledge) have tried.

I purchased and installed an ST rear seat bar within the first month of driving the 500e. With front wheel drive cars, I always prefer the feeling of having the rear do it's share of work in cornering rather than making the fronts do everything. A rear sway bar upgrade has usually done the trick in past vehicles so I did some reasarch and picked up the ST rear bar.

I took it to a shop to install because it actually required drilling into the chassis in order to mount the brackets, which put it beyond my DIY level. The drilling might make some people uncomfortable but I didn't have an issue with it.

Ive been glad that I did this upgrade because it did help with the cornering feel a bit. The car is ever so slightly more willing to turn in easier, but the impact wasn't as drastic as some other cars I've had in the past. I could say that I was expecting more of an impact to handling, but I definitely would repeat this mod without hesitation. I think part of the mismatch in my expectation is because the tire setup in the 500e is intended for fuel economy, and obviously not for overly spirited driving. Also, the electric motor makes so much torque that breaking loose the front tires is incredibly easy compared to my previous cars.

Does anybody else have any experiences with a rear sway bar on your 500e?

charrigan
07-17-2017, 07:29 AM
Keep an eye on the welds of the ST bar. They will eventually crack and or break. The multiple reports of the welds breaking made me look into other options. Due to abarth brackets being so over priced I resorted to designing custom rear brackets to accommodate an oem abarth torsion bar and the design can be tweaked to fit larger bars.

I have the brackets going on the cnc this week so ill be able to see if they clear the stock wheels and aftermarkets 15x7's.

compu_85
07-17-2017, 10:37 AM
Can you post some pictures of your car? I'd read that the 500 Abarth sway bar doesn't fit the 500e do to the battery fouling the location where the links attach to the bar.

-J

Fabio13
07-17-2017, 02:21 PM
I and others who have been on this forum for some years and with the ST Sway bar have had no issues. They will not crack and break. There was one bar in the earliest days that the owner said MAY have been cracked. There is only one hole on each side that needs to be drilled and it's pretty easy. You bolt the bar on with one bolt on each side and then drill though the other sway bar hole into the suspension arm. You don't even need to measure or mark the location, Comes with instructions. A set of plastic ramps helps to raise the car but isn't even necessary.

Immediately
07-17-2017, 08:49 PM
Theoretically if there was some breakage, how would you be able to tell from the drivers' seat? What would the signs be?

charrigan
07-18-2017, 07:50 AM
I and others who have been on this forum for some years and with the ST Sway bar have had no issues. They will not crack and break. There was one bar in the earliest days that the owner said MAY have been cracked. There is only one hole on each side that needs to be drilled and it's pretty easy. You bolt the bar on with one bolt on each side and then drill though the other sway bar hole into the suspension arm. You don't even need to measure or mark the location, Comes with instructions. A set of plastic ramps helps to raise the car but isn't even necessary.


for someone who has been on this forum for years im surprised you have ignored the multiple reports of ST bars cracking and or breaking. There were reports of one cracking as recent as this year. I spoke with that owner and it had been repaired twice. Another owner on a different fiat forum had one break off on the pass side. He repaired it, broke on the drivers side. Another owner had one break off under warranty, 2 months after installing the replacement BOTH sides broke off.

Mechanical basics 101 is you do NOT want a weld (a Chinese weld) being your pivot point on a torsion bar or a component that sees constant load cycling. It will fail. Its not a matter of if. Its a matter of when.

charrigan
07-18-2017, 07:55 AM
Theoretically if there was some breakage, how would you be able to tell from the drivers' seat? What would the signs be?


As far as driving feel you should be able to notice a broken weld because that component is no longer attached at both ends. Or you can simply inspect the welds for cracks.

The only proper solution for a rear torsion bar on the 500e is either retrofitting an abarth bar and brackets or the DNA adjustable rear torsion bar.

Sure the ST bar is inexpensive but its a poorly executed design with a major design flaw to keep costs down.

maximizese
07-18-2017, 12:36 PM
Be careful on uneven pavements (such as taking sharp right-hand turns up driveways, and driving over speed bumps on just the right-side or left-side tires). This creates an uneven load to the the rear suspension and the added rear sway bar negates the independence. Hence an uneven bump will load up the torque on the sway bar. I've experienced this with my 01 VW Golf TDI with the Autotech adjustable RSB. The end link bracket (aluminum) sheered off at the welds and also sheered at the bushing section. Luckily for me, Autotech is only 10 miles away and they were happy to give me a replacement.

My suggestion is to take uneven pavements slowly and to broaden your angle of entry into driveways (your front spoiler will thank you as well). Because my wife probably won't adapt to carefully driving with consideration for an added RSB, I'll refrain from installing one on the 500e. To reduce understeer, I'll consider getting matching wheels widths when the tires wear out.

27564

charrigan
07-18-2017, 12:54 PM
To reduce understeer, I'll consider getting matching wheels widths when the tires wear out.



just remove the hub pins and rotate the rears to the front.

maximizese
07-18-2017, 01:44 PM
just remove the hub pins and rotate the rears to the front.

That'll do. I'd want to try it out and take the car to the limit before having my wife drive it. Wheel spacers at the front would also reduce understeer, but I'm not doing that.

charrigan
07-18-2017, 01:58 PM
That'll do. I'd want to try it out and take the car to the limit before having my wife drive it. Wheel spacers at the front would also reduce understeer, but I'm not doing that.

its not a huge difference and doesn't create oversteer. it just lessens the intense understeer the 500e has.

maximizese
07-18-2017, 03:31 PM
its not a huge difference and doesn't create oversteer. it just lessens the intense understeer the 500e has. Good to know. I'll try it out when I get some new tires. My front tires probably have 5K miles left on them. Generally, it'll take a lot to get a stock FWD to oversteer. However, if and when you do it ain't pretty. It is far easier to reduce the understeer bias.

rkw
07-18-2017, 04:00 PM
its not a huge difference and doesn't create oversteer. it just lessens the intense understeer the 500e has.There's also the trick of higher tire pressure in the rear and lower in the front. If you're still on the OEM tires, they have terrible traction that would contribute to understeer. But I think "intense understeer" is overstated because it's worse in many (most?) cars.

Tweak
07-20-2017, 10:36 PM
for someone who has been on this forum for years im surprised you have ignored the multiple reports of ST bars cracking and or breaking. There were reports of one cracking as recent as this year. I spoke with that owner and it had been repaired twice. Another owner on a different fiat forum had one break off on the pass side. He repaired it, broke on the drivers side. Another owner had one break off under warranty, 2 months after installing the replacement BOTH sides broke off.

Mechanical basics 101 is you do NOT want a weld (a Chinese weld) being your pivot point on a torsion bar or a component that sees constant load cycling. It will fail. Its not a matter of if. Its a matter of when.

I can't provide links but I know of it happening at least a few times so it would be a concern worth keeping in mind and an occasional check on things cannot hurt.

lecarmat
07-21-2017, 08:24 AM
Not piling on, (maybe I am), I bought the ST around 3-4 years ago. LOVED it! For about 6 month's, and than, going, slowly, over a speed bump in my complex and BAM/POP, something in the rear snapped and was dragging!!!
Got out of my car and could see the driver side of the ST dragging on the pavement.

Pulled in to garage and removed both link's, driverside of course was broken off, and could see a long crack on the passenger side.
Contacted the vender, they did so the supplier, was sent a replacement very fast. Installed new, sent back old(pieces) and all good, much tighter feel than I had had in recent memory, prolly due to the old one cracking off, and "all good".

A few months later, going down a street with a speed bump (35/40 MPH), BAM/POP, this time one side let loose, bar dragging and FAR from home. Removed remaining bar, threw it (foolishly) away. Im sure I would have been able to get replaced again by warranty, just frusterated.

Recently installed another bar (RRM), beefier and robust links and again, "all good".

The ST bar was great looking, fairly easy to install, and had great customer service when the bar failed, but it did, twice.

Immediately
07-22-2017, 06:16 PM
Not piling on, (maybe I am), I bought the ST around 3-4 years ago. LOVED it! For about 6 month's, and than, going, slowly, over a speed bump in my complex and BAM/POP, something in the rear snapped and was dragging!!!
Got out of my car and could see the driver side of the ST dragging on the pavement.

Pulled in to garage and removed both link's, driverside of course was broken off, and could see a long crack on the passenger side.
Contacted the vender, they did so the supplier, was sent a replacement very fast. Installed new, sent back old(pieces) and all good, much tighter feel than I had had in recent memory, prolly due to the old one cracking off, and "all good".

A few months later, going down a street with a speed bump (35/40 MPH), BAM/POP, this time one side let loose, bar dragging and FAR from home. Removed remaining bar, threw it (foolishly) away. Im sure I would have been able to get replaced again by warranty, just frusterated.

Recently installed another bar (RRM), beefier and robust links and again, "all good".

The ST bar was great looking, fairly easy to install, and had great customer service when the bar failed, but it did, twice.

Wow, thanks for sharing your experience. So on the two occasions when this happened, there was no ambiguity of whether or not something was broken, I assume? I've gone over a few aggressive speed bumps and have not yet had any loud pops or dragging occur. If something had gone wrong it seems like I should be able to know rather quickly.

lecarmat
07-23-2017, 09:33 AM
So, when the bar failed the first time I had just pulled into my parking lot, up a small entry ramp(at a small angle) and over a speed bump, at 45 degree angle. Meaning the rear wheel's came over at slightly different time's and the bar stressed.

The POP/BANG was the driver side weld breaking through and the now loaded bar hitting the pavement. As I was 10 feet from my garage I pulled in.Removing the bar from the passenger side and inspecting it I could see that both welds, the now totally failed driver side and the passenger side had fairly long crack's. Also both side's crack's had a fair amount of rust, indicating they had been failing for awhile.

The second bar that was replaced under warranty broke when I was far from home, again driver side 1st. Figuring thee passenger side had cracked, and having no tool's , and more than a little annoyed, I was able to twist the remains passenger side weld off.

Now, in retrospect the only indicators that something was going amiss was going over bump's, up ramps, and uneven surface's, at angles(meaning not perpendicular and the rear wheels would go over at different times) might be a groaning noise. Didn't pick up that this was something to be concerned of.

My Sport is lowered on Eibach spring's with ABARTH shock's in the rear, so can't say that hasn't contributed to anything.

I had considered the DNA sway bar, just a beautiful piece, but by the time the urge to put another sway bar on it was NLA, at least at MADNESS.

I recognize that everything wears out, suspension parts too, and it's reasonable to assume a sway bar (or it's components) would eventually fail. I guess I would want closer to 4 or 5 year's before full failure.

AND, it would not hurt to inspect the bar from time to time, the bolt's and the weld's.

Anyway's that's my experience.27615

maximizese
07-23-2017, 01:48 PM
So, when the bar failed the first time I had just pulled into my parking lot, up a small entry ramp(at a small angle) and over a speed bump, at 45 degree angle. Meaning the rear wheel's came over at slightly different time's and the bar stressed.

The POP/BANG was the driver side weld breaking through and the now loaded bar hitting the pavement. As I was 10 feet from my garage I pulled in.Removing the bar from the passenger side and inspecting it I could see that both welds, the now totally failed driver side and the passenger side had fairly long crack's. Also both side's crack's had a fair amount of rust, indicating they had been failing for awhile.

The second bar that was replaced under warranty broke when I was far from home, again driver side 1st. Figuring thee passenger side had cracked, and having no tool's , and more than a little annoyed, I was able to twist the remains passenger side weld off.

Now, in retrospect the only indicators that something was going amiss was going over bump's, up ramps, and uneven surface's, at angles(meaning not perpendicular and the rear wheels would go over at different times) might be a groaning noise. Didn't pick up that this was something to be concerned of.

My Sport is lowered on Eibach spring's with ABARTH shock's in the rear, so can't say that hasn't contributed to anything.

I had considered the DNA sway bar, just a beautiful piece, but by the time the urge to put another sway bar on it was NLA, at least at MADNESS.

I recognize that everything wears out, suspension parts too, and it's reasonable to assume a sway bar (or it's components) would eventually fail. I guess I would want closer to 4 or 5 year's before full failure.

AND, it would not hurt to inspect the bar from time to time, the bolt's and the weld's.

Anyway's that's my experience.27615

It sounds like we've had the same experience but in different cars. My 01 VW Golf RSB had the same fate as yours doing the same thing. I was going up a driveway at about 20mph and the uneven load torqued up the driver side end-link. I heard and felt a thud and both the bracket and the bushing sheared.

#8 (http://www.fiat500usaforum.com/showthread.php?29031-ST-Rear-Sway-Bar-Impressions&p=806038&viewfull=1#post806038)

aelfwyne
07-23-2017, 10:55 PM
When I had my 500 Sport, I installed the ST Sway bar at about 5,000 miles. 27000 miles later (at 32k miles) I sold the Sport and the ST Sway Bar was just fine, no cracks/breaks. Sold it to a guy with a 500T and a year after that and a second trip to the Twisted Sisters run, still no cracks/breaks. Haven't spoken to him recently so I don't know if it's still running fine.

It's not a guarantee these will crack. Those who had it happen, yeah it sucks. May be that there is a quality control issue.