Steeda S550 Mustang Extreme G-Trac K-Member Brace (2015-2021)

43 Review(s)
$30.00 (15%)
Steeda's Extreme G-Trac brace for 2015+ S550 Ford Mustang 5.0L GT, 2.3L EcoBoost, & 3.7L V6 provides greatly improved front chassis rigidity, tighter handling suspension & firmer steering. Manufactured from the best super strong chrome moly steel.
Part Number: 555 5532
If Anderson Composites product is delivered defective or damaged, you must notify Steeda within 24 hours of delivery.

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Steeda's S550 Mustang Extreme G-Trac Brace (k-member brace) for 2015+ Mustang GT, EcoBoost, and V6 are a direct bolt-on addition to your S550 Mustang and provides greatly improved front chassis bracing.

Steeda's S550 Mustang Extreme G-Trac Brace for 2015-2019 Mustang GT, EcoBoost, and V6 mounts close to the control arm mounts, and helps strengthen the connection between the control arm mounts, and the rear of the subframe. This makes the load path more direct, and gives much more effective stiffening, so the suspension geometry doesn't change during high cornering/chassis loads. Manufactured from super strong chrome moly, alloy steel tube, making it over twice as strong as any mild steel offering.

Note: This brace does not fit 2018 Ecoboost with A10 auto trans or GT350. GT350 owners should purchase 555-5533 instead.

Purchase your Steeda S550 Mustang Extreme G-Trac Brace for your Mustang GT 5.0L, EcoBoost 2.3L, and 3.7L V6 at Steeda Autosports today!

Product Benefits
  • Improves suspension compliance
  • Also referred to as k-member brace
  • Stiffens front subframe
  • Bolt-on installation
  • Clears long tube headers!
  • 15% lighter than the competition

CA Residents: Cancer and Reproductive Harm WARNING

Hi everybody Brian from here today to speak to you about our G-Trac Braces for the front of your S550 Mustang. Like many auto manufacturers Ford assembles the current Mustang in pieces. They put the rear subframe together and its components and then the front subframe together and its components and obviously assemble the car. Now when we're putting the front subframe together the subframe itself actually is pretty wide at the rear mounting points and the reason they did this is that it could accommodate multiple engines, of course the Coyote 5 liter the EcoBoost as well as the v6 in the earlier S550,models but those bolts being so far apart allow the body to kind of flex and kind of roll. We have two solutions for this that will tie that in and the benefits to this are sharper handling, better chassis feedback and more effective use of even the factory suspension or any aftermarket suspension you throughout the car. Let's begin with our Ultralight Two-Point G-Trac Brace. Now again this connects the two outermost points. We construct this of chromoly tubular steel in particular to rectangular and the reason we do this is because we want to use a lightweight material but we also want to have enough surface area to really stiffen up the front of the car, again to improve handling and chassis responsiveness. For you GT 350 owners this is the right application for you and for some of our GT owners that have long tube headers this may also be the right choice for you. If you have questions about fitment please reach out to us. Now for you corner carver's out there, we offer an Extreme G-Trac Brace this mounts in four points and triangulates those four points just like our Ultralight G-Trac Brace our Xtreme G-Trac Brace is made of chromoly tubular steel now we went to a tubular steel because we have four points to distribute the load this also means that even though there's more material it's lighter weight 15% lighter than the competition. Both of our braces come with all the hardware required for installation and they don't require any modifications to the car. Furthermore we realize that the subframe is actually a stamped tubular steel and that when you tighten the bolt and a nut against it can actually crush down so we've also provided inserts to prevent that from happening. Again taking things one step further than our competition to ensure that you have a great handling car. Furthermore these are powder-coated for durability and we back them with our Steeda lifetime warranty. They're manufactured in the USA at our Valdosta Georgia manufacturing facility because Speed Matters. So which one is right for you the Ultralight Two-Point or the Extreme Four-Point G-Trac Brace. if you have any questions or comments about this video please feel free to post them below. If you enjoyed the content please click like and share with your buddies. Be sure to subscribe to our YouTube Channel. If you'd like to learn more about these and many of our other great products visit and don't forget to follow us on social media most importantly have a great day!
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Fitment & Features


Manufacturer: Steeda Autosports
Made in USA: Yes

Installation Information:

Level of Difficulty: Medium
Install Time: About 1 Hour
Tools Required: Basic Shop Tools
Print Instructions: Installation Instructions
Install Video:

Vehicle Fitment:

Fits Model Year: 2015, 2016, 2017, 2018, 2019, 2020, 2021

Customer Reviews

Rating Snapshot

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Average Customer Ratings


A must for every mustang!
I was a little skeptical of how good this product could be at first. Reading the reviews I couldn't believe that a little piece of metal could make that big of a difference, boy was I wrong. As for the installation it couldn't have been easier. It took me and a friend 1 hour to install using jack stands. I did need to go out a purchase a T60 torx bit but I needed one anyway. Now, to get into the performance gains. Off the bat I noticed a huge difference in steering feel. It felt sharper and a little more firm. Its hard to explain exactly what the K member does in words but think point and shoot. If I turn the steering wheel in a direction it immediately goes in that direction. No flex, no weight shifting, just pure grip and turning. It really does make your mustang hug corners. In addition, the accuracy of the steering wheel was improved. You can really feel the road in your hands. The ride quality was actually improved because it makes the suspension do the work not the chassis. However, I am still on stock suspension so If you are lowered or on sport suspension you might notice a slight increase in harshness. Regardless, you didn't buy a mustang to have a comfy ride:). This is a MUST HAVE for every mustang! Steeda, well done!
Did you find this helpful?  3 of 3 Found Helpful
Verified Buyer   from Clemson, SC on 10/12/2021
2015 Mustang GT Extreme G-Trac Brace
Installation was simple with the supplied hardware. I chose to keep the brace mount internal spacer installation rods. I just bent them up into the installation hole to hopefully give me some way to keep the spacers from shifting if I have to take the brace off. Handling wise, I did note the car has much less body flex/roll when cornering hard. It has added more capability to my daily driver without an increase in road noise or harshness to the ride.
Did you find this helpful?  7 of 7 Found Helpful
from Temecula, CA on 3/17/2021
Very Nice
Worth the time, money, effort spent. Suppression is more positive, car rolls easier. The car is a PP2 was pretty good as it was, now crisper . Well done Steeda ......... !!
Did you find this helpful?  5 of 5 Found Helpful
from woodstock on 2/28/2021
Must-have Mod!
Install was pretty easy. Everything lined up well and all hardware fit perfectly. Took the car for a quick ride and I couldn't believe how much tighter the front of the car is. It was already pretty good with the PP1 package and magneride, but there's a huge difference in turns. Everything stays flatter now with no roll in the front. This brace and the subframe braces and jacking rails should have been stock from Ford. They completely change the car for the better.
Did you find this helpful?  10 of 10 Found Helpful
Verified Buyer   from Homer Glen, IL on 1/31/2021
Installation Tips!
Great product quality. The fit was not perfect for me, but I got it in with effort. These tips might be helpful: 1 - A 22mm wrench or socket is not necessary because a 7/8 fits fine. 7/8 = 0.875 in., 22mm = 0.866 in. 2 - Loosely hang the rear mounts with small C-clamps. They stay in place if you run the clamp screw down into the bolt hole a little, yet remain totally moveable for getting the front mounts up in place.3 - Tape the spacers on top of the front mounts! When one fell off inside the frame, it was really hard to fish it out.
Did you find this helpful?  12 of 12 Found Helpful
from Texas on 11/7/2020
Extreme Brace Install
Great quality and well built. Installed the brace and everything fit great. After a cruise through the Tail Of Dragons, I noticed how must better the car handled, felt solid in the corners. So glad I installed it!
Did you find this helpful?  7 of 7 Found Helpful
from Greer on 8/14/2020
New suspension parts
Today August 1 I had the minimum drop lowering springs, the front and rear sway bars, the Gtrack brace and strut tower brace installed on my 2019 base non ppGT. These were all installed by Mustang Magic on Long Island. I have to say I'm in love with the car again.The car is so much more responsive with these parts installed and I haven't even had an alignment done yet the alignment shop was closed by the time everything was installed. The strut tower brace hasn't arrived yet so I imagine that will tighten up things even more. Steeda thank you. You have made my car even more fun to drive and I did't think that could be done. The parts look great they are obviously built great and they function as promised. Anything suspension that goes on my car will come from Steeda you have a customer for life thank you
Did you find this helpful?  10 of 11 Found Helpful
from Long Island New York on 8/1/2020
Arrived within a few days. Packaged very carefully
install was 20 minutes maybe and that's unpacking it as well. Perfect fit and install was a no brainer. These guys are always professional and have the experience to guide you through your build. Unlike lots of places They won't try to up sell you something that isn't practical for your project.
Did you find this helpful?  7 of 7 Found Helpful
Verified Buyer   from Maine on 6/28/2020
Extreme G trac brace
Another great product from Steeda. Fit and finish are superior.As others have stated, make sure you take time to remove factory stamping slag/burrs before attempting to install. Be ready to manhandle the brace into position: you will find one or two fasteners can be very loosely started and then use a transmission jack to hold it in place while lining up other fasteners.
Did you find this helpful?  6 of 6 Found Helpful
Verified Buyer   from Ohio on 6/5/2020
Perfect fit once again
As a long time customer of Steeda, I keep coming back year after year, car after car. Maybe more $$$ than parts made in China, but there is no comparison on quality. I installed the brace with the car on jack stands/ramps. You don't need a lift. It's an amazingly simple install. If you don't know a torque wrench, just borrow one. Same with the 12 mm allen socket. Installation took maybe 30 minutes. Everything lined up exactly. It could not have fit better if Ford made it. Since I just recently installed it, I cannot yet comment on the change to my car. However, I expect it will perform exactly as designed, because that's what Steeda does. My only wish would be that Steeda offer the 12 mm allen sockets on their site as an add-on to the purchase. Took me 3 stores to fine one.
Did you find this helpful?  11 of 12 Found Helpful
Verified Buyer   from Georgia on 10/26/2019
No Brainer Purchase and Install
The entire experience from purchase to torquing the last bolt was a 4 out of 5 star rating for me. Your experience may be much better. #1. Steeda, no issues to report. Shipping / signature required a little annoying. Packaging was first rate. Product arrived with the supporting hardware neatly and thoughtfully packaged. Very impressed. (See pic) Same goes for the jacking rails I purchased. I also like that the product is made in the U.S.!!! #2. Install. My 2018 GT had clearance issues related to the spacers. Excess metal inside the control arms had to removed with a large flat head screw driver and a hammer in order for the spacers to be installed. This took up the bulk of time for the install. Made the install a little challenging, but not aggravating. (Side note. Part of the reason I bought my car was with the intention of occasional weekends being spent in the garage adding upgrades). #3. Tools required. The sizes of the included hardware are something to make note of before you dive into the install. Assuming your a DIY wrencher like me. The main issue is being able to properly torque the bolts. My tool collection is pretty decent. However, I found myself having to purchase a 22mm wrench and a 1/2-inch drive x 12 mm hex bit. I used a bolt head to get the front bolts installed. #4. Results. My initial impression is similar to other post about the handling after install. Took a brief drive around my neighborhood, and the front end definitely seems more solid. More miles are need in order to provide a more informed opinion. However, so far so good. Keep up the good work Steeda!
Did you find this helpful?  17 of 19 Found Helpful
Verified Buyer   from on 10/13/2019
G trac brace
Great product but in case a pain to install on jack stands if u have lift would be better Steeda has good product
Did you find this helpful?  5 of 11 Found Helpful
Verified Buyer   from Haines City on 8/21/2019
Noticeable improvement
The 4 point brace is a remarkable improvement. You wouldn't think something so subtle would change much but you could definitely feel a change in the precision and response of the steering. I had a tendency to under steer the car and go wide through turns. I'm sure a habit of driving my previous Mustang for 14 years and being used to thag steering response. Adding the brace has improved this substantially and have no issues. Install takes a bit of time and can be frustrating to line things up. I loosely bolted the back half of the brace, loosely bolted the passenger side front and eventually got the driver side pulled over enough to fit it. Just a method that works for me.
Did you find this helpful?  25 of 25 Found Helpful
from Georgia on 6/12/2018
Extreme G-Trac Brace
One of the best mods I've done yet, completely changed the way the front end handles corners! Super easy install as well.
Did you find this helpful?  12 of 13 Found Helpful
Verified Buyer   from on 6/12/2018
Steeda does it again!!!!!
Love love love this brace. Was looking for a way to tie up my front end for turning into corners on the track! This installed easy with all the supplied hardware and I could immediately feel the difference the first turn I took! Cleared my long tube headers!! If you run your car through the turns of the mountains or the racetrack you NEED this on your mustang
Did you find this helpful?  20 of 20 Found Helpful
from Acworth on 6/12/2018
A ton better
The car drove a ton better with the Steeda sway bars, strut brace and g-brace, than with the stock sway bars. With the stock sway bars it understeered a ton and if you tried to make it turn with the throttle, it would push the front tires more or just finally snap the backend loose. With the Steeda sway bars, I had the front bar on next to the stiffest setting and the rear bar was on the stiffest setting, the car was real neutral and flat, if I drove in to hot I could make it turn with a little more throttle and was easy to control it that way. One of the runs I tried to drive thru a little S section into the salom part of the course wide open in second and hung the back end out side ways at about 60 mph and I just put both feet in for a second and brought it back around and still made it thru the salom. If that would have been the stock bars it would have spun around and took all the cones with it.
Did you find this helpful?  12 of 12 Found Helpful
from New York on 11/21/2016
Car feels 200lbs lighter up front!
Really happy to have gotten the G-Trac. What a difference up front! My car is not a PP car but I do have my buddies PP strut tower brace (he supercharged his car so it wouldn't fit anymore) and together with the G-Trac it was an amazing difference! Car feels 200lbs lighter up front!
Did you find this helpful?  12 of 12 Found Helpful
from Mississippi on 11/1/2016
A big thumbs up from me, really tightens up the front-end exactly as it should do
G-trac brace is a big thumbs up from me, really tightens up the front-end exactly as it should do, identical to the effect it had on the S197 chassis. Car feels a lot more direct, changes direction better and I think the car has a little more feel as well. Definetely a modification worth while doing, even if a little more tricky to fit on UK cars. The front-end on this car is absolutely superb.
Did you find this helpful?  12 of 12 Found Helpful
from United Kindom on 10/15/2016
The control of the car is incredible
With the G-trac brace and subframe braces, WOW...The control of the car is incredible. The turn-in is truly lightning fast. I am running 285's up front so that helps a bit but that G-trac brace really increased this with those springs. The just slightest twitch on the steering wheel, the car starts to go that direction and I mean just the slightest.
Did you find this helpful?  11 of 11 Found Helpful
from Oklahoma on 7/8/2016
Was well worth the investment
Mine feels very planted, no hop or stepping out when I give it the beans to pass (or just be a road hooligan - LOL). Was well worth the investment IMO.
Did you find this helpful?  11 of 12 Found Helpful
from California on 6/10/2016
The front feels like it rides on rails
Installed my Steeda G Trac Brace and Steeda IRS subframe brace. Car feels completely different now. Way more composed and even rides more smoothly over all the poorly paved roads and potholes in south east PA. The front end feels like it rides on rails now with the g trac and FRPP strut tower kit. G trace took about 20 minutes.
Did you find this helpful?  11 of 11 Found Helpful
from Pennsylvania on 4/28/2016
Handling fantastic
Their progressive lowering springs, g-trac brace and axle-back exhaust have this car running smooth as hell, handling fantastic and sounding like an exotic muscle car if that makes any sense.
Did you find this helpful?  6 of 7 Found Helpful
from Texas on 4/9/2016
Still love it
I've owned a base ecoboost and now I own a performance pack ecoboost. I have steeda irs frame stiffeners and the front g-trac bar. I had them installed on both cars and the pp car vs the base is a WORLD apart on the way it handles. Yes the ride isn't as soft as the base but it doesn't bug me, I still drive the car daily and still love it. I have the steeda jacking rails on the way and after that it will be one of the suspension kits next. I want the car to handle on rails. It's just the way I feel about it. Hope this helps
Did you find this helpful?  6 of 6 Found Helpful
from Florida on 3/27/2016
The car feels so much more planted to the road
This is the first time I've ever done anything suspension wise to my car, David @ Steeda helped out greatly with all my questions as well as getting me setup with an install at their Pompano location with a tour of some badass shop cars and their facility. Everyone @ Steeda - David, Patrick, Matt were great and made sure I was happy with everything. I can't recommend their shop enough to anyone in the area and Matt did an awesome job with everything on the install, even tack welded my Gibson exhaust and turned their clamps a bit to help out. I won't have a chance to do pics this weekend of my spot on the beach as that will give a good before/after comparison when I put them together. The car feels so much more planted to the road, even just turning out of their parking lot I could tell everything felt more connected and precise to what I was telling the car to do. It basically now goes where I want it instead of reacting to what I'm asking it to do if that makes any sense at all? I had some open highway and did a little bit of careful back and forth in my lane and I felt completely planted and not bouncing around back and forth in my seat. Almost found myself doing slalom in between some construction barrels but given how my morning went I decided against it. The springs give the car the look I wanted and make the Vossen wheels look that much better. Nice tighter rebound than stock PP springs and reduces the overall bouncy ness on some of those highway stretches where it feels like you're hitting hydraulics for a half a mile. Also any bridges or overpasses with rough spots where you enter/leave them were solid. The MT-82 bushing insert is noticeable and I had much easier downshifts for highway passes on the way home, feels like a much more solid shift that I had to get a bit used to in a good way. I didn't do any hard launches or try to break the rear end loose at all since I was just getting used to it, will report back later on that. I can't really report on some of the individual IRS components since they all went in at the same time, but I am noticing a slight (and I mean slight) gear wine from the rear with the Black bushings. It's only really noticeable if you try to make it happen and barely push the gas at cruising speed. Nothing I'm worried about and after 4 hours of driving it home windows down and up for a few sprinkles it does not bother at me all. It's not all the time either or in any specific gear so no biggie as far as I'm concerned.
Did you find this helpful?  8 of 8 Found Helpful
from Florida on 3/27/2016
Noticed improvement in cornering feel
I have added the Steeda tower brace and extreme g-trac lower brace. I don't plan to autocross, but I do like to rush through a corner now and again. I noticed improvement in cornering FEEL. Whether this translates to faster cornering speed or not, I haven't checked. The best I can explain the change in feel - It's like upgrading your tires to a stiffer sidewall/lower profile. There is less chassis compliance and spongyness mid corner to confuse my brain that I'm close to the handling limit.
Did you find this helpful?  10 of 10 Found Helpful
from Kansas on 3/1/2016
There are no reviews for this product!

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