Steeda S550 Mustang IRS Subframe Bushing Support System (2015-2023)

41 Review(s)
$15.00 (9%)
Steeda S550 mustang IRS subframe bushing support system for your 2015+ Mustang GT, EcoBoost, and V6 gives the rear end a solid feel with no increase to NVH. The Steeda IRS subframe bushings eliminate rear subframe bushings eliminate subframe movement.

Part Number: 555 4437
Write a Review

Suggested Mods


This Steeda S550 Mustang IRS Subframe Bushing Support System for your 2015+ Mustang GT, EcoBoost, and V6 are made from CNC machined, 6061 aluminum.

These Steeda S550 Mustang IRS Subframe Bushing Support System for your 2015+ Mustang GT, EcoBoost, and V6 gives the rear end a much more solid feel with no increase in NVH at all. The Steeda IRS Subframe bushings eliminate rear subframe movement notorious in the 2015+ Mustang GT, EcoBoost, and V6. A stiffened subframe allows the car to increase traction to the rear wheels and is the first step towards eliminating wheel hop.

The Steeda S550 Mustang IRS Subframe Bushing Support System for your 2015+ Mustang GT, EcoBoost, and V6 are easy to install, with basic hand tools. The Steeda IRS bushing kit also does not require any permanent modifications to the car.

Note: Does NOT fit the GT350 or Mach 1, but will fit the GT500. If you're looking to purchase this kit for your GT350 or Mach 1, then check out 555-4449.

PATENT NO.: US D784,881 S

Purchase your Steeda S550 Mustang IRS Subframe Bushing Support System for your 2015+ Mustang GT, EcoBoost, and V6 at Steeda Autosports today!

Product Benefits
  • 10 piece kit
  • Increases traction
  • No increase in NVH
  • Easy to install
  • No permanent modifications
  • Limited lifetime warranty

CA Residents: Cancer and Reproductive Harm WARNING

Hi everybody Brian from Here today to show you our Subframe Bushing Support Systems for the S550 Mustang. The purpose of our Subframe Bushing Support System is to reinforce the bushings in the rear subframe. Now as we've talked a lot about Ford used a soft durometer bushing and a lot of points on the Mustang including the four main mounting points of the rear subframe. Now this is one of the areas that induces wheel hop and as always we're working on ways to take that out of the car and make it a better driving experience for you. Now the way these work is, they actually sandwich the factory bushings and reinforce them thus the name. They reinforce them by filling in some of the gaps in those soft bushings. This will help reduce the subframe from wanting to move up and down as we've shown in our other videos and that's part of what induces the severe wheel hop under hard acceleration. Despite reinforcing the factory bushings these don't add any NVH or noise vibration or harshness and the way that we can do this is, we retain the factory mounting points at the tops of each bushing. Now this is really important because the Ford engineers designed a key engineering aspect into their factory bushings and those are these kind of teeth or knurls at the top of the bushings and these are what help keep the subframe from wanting to walk under the car on your hard acceleration, hard launches or hard cornering. So it's important to retain those and not cap those off like some of our competitors do. We've constructed these out of aluminum which is lightweight, strong and weather resistant. They also carry our lifetime warranty and we proudly manufacture these in the USA at our Valdosta Georgia facility. If you have any questions or comments please feel free to post them below. If you enjoy the content of this video be sure to like it and share with your friends, as well subscribe to our Youtube Channel. Learn more about these products and many of the other products we offer at and don't forget to follow us on social media. Most importantly have a great day!
View Full Transcript

Fitment & Features


Manufacturer: Steeda Autosports
Made in USA: Yes

Installation Information:

Level of Difficulty: Tech Recommended
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, 2022, 2023

Customer Reviews

Rating Snapshot

Select a row below to filter reviews.


Average Customer Ratings


Wheel Hop FYI on Install
I just put this in and it appears to have taken my wheel hop away. A suggestion for those installing these is that when installing the bottom rear ( the hard one ), install from the rear so you can tap it in. I tried from the front as it was sliding in easier but you cannot get any leverage to get it rotate around the bushing. I wasted about an hour trying to install from this side when I went and watched several of the video's again when I saw it was installed from the rear. It should be pointed out in the video just an FYI. Thanks for the products they are made very well.
Did you find this helpful?  10 of 10 Found Helpful
Great for Whipple 350
Gotta give this 4 stars because 2 of the pieces that connect together (4 individual) do not fit the GT350. This needs to be highlighted and bolded on this page and on the Stop the hop kit page. NVH hasn't changed much at all.Substantially helps get the power down on my 750whp GT350
Did you find this helpful?  6 of 17 Found Helpful
Verified Buyer  
Excellent Product!
These bushing were easy to install, (lubrication helped) and have had no noticeable increase in NVH after driving for 100 miles (I'm sure they can last for 100,000). Accelerating from a complete stop or out of a turn has become very satisfying due to the ease with which the power is put down. The confidence is inspiring. These really are a great addition to any suspension setup!
Did you find this helpful?  7 of 7 Found Helpful
Verified Buyer  
Bye, bye wheel hop!
Today I added the Steeda Rear IRS Subframe Support Braces and Bushing Support system. It really made a difference stiffening up the suspension. I will install the Steeda Vertical Links next week. Bye, bye wheel hop!
Did you find this helpful?  2 of 2 Found Helpful
Tracks like a go kart now
On my previously stock GT non-PP i had a odd sensation while cornering that could best be described as a rubber-band feeling. I believe it was compliance of the subframe bushings. It was unnerving. Felt like the start of the tires breaking loose - but it wasn't. I installed the Steeda rear IRS bushing support kit and the IRS braces and the sensation went away. Much improved cornering afterward. I was inspired by the improvement so I added the Steeda springs and swaybars. Tracks like a go kart now.
Did you find this helpful?  13 of 14 Found Helpful
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?  1 of 1 Found Helpful
One of the biggest improvements to the handling of the car
One of the biggest improvements to the handling of the car is definitely the Steeda goodies all thanks to David here on the forum. He helped me so much picking out everything I should upgrade for all of the suspension parts to make this a great daily driver but also be able to take turns comfortably at high speeds and put the power to the ground. One of the first Steeda upgrades Slammered threw on for me was the Front/Rear Sway Bars and the IRS Support Brace and damn did it make a pretty damn noticeable difference in turning. No I don't track this car as of right now but the closest I get to taking turns and curves is off ramps from the highways and I've done decent speeds coming through those turns. The sway bars help keep the car planted and definitely boost the handling capability that the IRS already provides. I also installed the billet mounts and they look damn good with the blue sway bars and definitely are top notch quality over the stock mounts from Ford. Wheel hop has been one of the most notorious things the S550 platform has encountered with the new IRS system. Wheel hop is a No no and Steeda's IRS bushings are definitely the first step to knock out way more than 50% of the notorious wheel hop. When taking the bushing out of the box and taking a peek at my new goodies, I was amazed of the quality that is put into the manufacturing of the parts Steeda offers. IRS Bushing from Steeda is a must if you're looking to eliminate more the 50% of the wheel hop. It's great quality and definitely helps put the power to ground. When hitting it and shifting from 2nd to 3rd it's a whole new feel and it just takes off.
Did you find this helpful?  2 of 2 Found Helpful
This is the way the car should be with the PP
Since I was going to have the car up on jack stands in my driveway, I figured I'd do just about everything at once. Installed the Steeda IRS subframe bushing supports, alignment inserts, differential bushing supports(black), transmission bushing insert, and the Steeda shifter base bushing bracket along with the FR touring cat back. I had to have the upgraded bushing in the knuckle done at the Ford dealer. The bounce is gone! This is the way the car should be with the PP.
Did you find this helpful?  1 of 1 Found Helpful
What an amazing difference
Installed the Steeda IRS Subframe Alignment Bushings, and Steeda IRS Subframe Bushing Support this weekend. What an amazing difference, and not too difficult of an install. I definitely recommend anyone that is thinking about these to knock them out at the same time.
Did you find this helpful?  0 of 2 Found Helpful
I definitely recommend as an upgrade to the S550 Mustangs
The bushing support system is a great start to improving the IRS suspension. The rear end feels a little bit more stable and there is no increase in NVH as stated by Steeda. Wheel hop has diminished when compared to stock and made a big difference. When starting from a stop hard the car use to get bad wheel hop that was violent, it felt like something would surely break. Now with the bushing support system I do not get the violent wheel hop. I definitely recommend as an upgrade to the S550 Mustangs. Great job Steeda!
Did you find this helpful?  2 of 2 Found Helpful
This is definitely worth the purchase
I installed this a few days ago and the rear end feels a little bit more stable and it has helped reduce wheel hop. This is definitely worth the purchase! I will be adding more Steeda parts to my car soon.
Did you find this helpful? 
It's a HUGE difference from the relatively vague/floaty stock PP setup
The G-Trac brace made a big difference in ability to turn in with exactitude on my PP-equipped GT, albeit modified with Steeda springs and sways. The back end of my car got where I needed it with Steeda springs, sways, bushing mounts and vertical links. The car now steers beautifully, doesn't roll, doesn't pitch on acceleration or dive under braking, and the front-to-rear grip is matched, yielding great confidence to place the car right where you want it on corner entry, mid turn, and exit. The G-Trac brace's effect on steering was both noticeable and transformative. It's a HUGE difference from the relatively vague/floaty stock PP setup. I'd say it even rides better without those stock PP undulations. I did not feel the need for the rear brace after the bushing mounts and vertical links (put on after everything else), but that's not to say that the chassis wouldn't improve yet more from it; I'm still considering doing it. It's just that the car feels perfect right now for hard-ass canyon carving and everyday use.
Did you find this helpful?  4 of 4 Found Helpful
Install is very easy and you don't notice any difference in ride comfort or noise
Install is very easy and you don't notice any difference in ride comfort or noise. However, while I did these the same time as Eibach Sportlines, they stand out on their own. Launch the car and you can notice a difference in deflection.
Did you find this helpful?  2 of 2 Found Helpful
I now have ZERO wheel hop!
I forgot to update this after installing the Steeda springs and wheel hop kit, I've had them on for a couple weeks now. I'm loving the look with the springs, and there is definitely a noticeable difference in handling. Ride quality suffers a little, but it's not terrible. The wheel hop kit (IRS subframe bushing support system) does exactly what it's advertised to do, I now have ZERO wheel hop!
Did you find this helpful?  3 of 3 Found Helpful
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?  2 of 2 Found Helpful
The handling of the car is just perfect
I am beyond please with everything that Jamie did for the installation and alignment. David was an absolute pleasure to deal with in buying and setting up the appointment for me. Everyone at Steeda has been a joy. The car has been completely transformed. The ride quality with the progressive springs is 3 times better vs. the stock GTPP springs. The handling of the car is just perfect. It is so, so flat now when pushing the car hard in any type of turn. Brake dive has been greatly reduced. I would say by 80-90%. I can mash the brake pedal and it just stops, so tried and true. The front-end barely dives at all. This is from 70-75mph and just mashing the pedal. It truly begs for more speed when entering turns. Of course, this only on roads and not a race track or autoX course. Wheel hop has been greatly reduced. I still have a couple more parts to order to virtually eliminate it all together and those will be ordered at a later date. Shifting hard to 2nd gear, I just now get wheel spin and no hop. Only time I get a little hop is via a hard launch. But again, it is greatly reduced and doesn't happen all the time. The car is so quiet, no increase in NVH in anyway. This has been some of the best money I have ever spent on any car mods, PERIOD. Their parts deliver what they promise and produce outstanding results. Anyone on the fence, I highly recommend you go ahead and purchase their stuff.
Did you find this helpful?  1 of 1 Found Helpful
A great compliment to the performance package
First impressions, car is handling very good on michigan roads! I cannot go full out performance driving because I did paint my brake calipers as well, ended up being a little short on brake fluid after bleeding all of the air out of the lines, anyways! Overall, a great compliment to the performance package, I am very happy that they maintained a linear rate instead of the progressive rates from others. Went over a few super bumpy horrible gravel filled roads, car actually feels more comfortable for some strange and weird reason. Gave it a little gas on first gear and the car does not squat nearly as much and it does not nose dive nearly as much, swinging the steering wheel back and forth and the car does not act like its twerking anymore so that is awesome. I also installed the steeda subframe bushings as well, so maybe the two were a potent combo! Rear subframe braces are on the way so I'll give you a full Review of everything once they are all on and the car had an alignment, go pro video to come! Also, a teaser of the brakes I did myself
Did you find this helpful?  1 of 1 Found Helpful
Honestly, the fitment is so unbelievable
Added even more STEEDA!!! IRS Brackets and Centering spacers. Lucky for me, we set the IRS properly and the centering spacers went right in, easssyyy. The brackets also went right in. I had a slight snag with the front OE bolt, WD40 did the trick. All looks unreal. Spent the day washing both my cars, so no driving impressions, but I just love the idea that everything is so fastened. Honestly, the fitment is so unbelievable, that sometimes I think Steeda help develop the car. lol.
Did you find this helpful?  1 of 1 Found Helpful
What more can you ask from such a simple mod?
Easy to install, got rid of 90% of the dreaded wheel hop on the street, and really sured up the rear end hard into corners. What more can you ask from such a simple mod?
Did you find this helpful?  3 of 3 Found Helpful
The car is showing zero wheel hop
Been on vacation the last week but I had a chance to hit the track last night. Wasn't planning on making any passes but it was dead and the cars that were making passes were hookin' really well so I decided to make a few. Unfortunately I didn't have the laptop with me to log the passes. First pass I left soft. 2000 RPM and no 2-step. Car hooked and zero wheel spin or hop. Hooked well enough that it bogged a bit off the line. Second pass. 3000 RPM on the 2-step, no launch control just RPM mode. Car dead hooked. No spin, no hop. Again, hooked well enough to bog the car a bit. Third pass. 3200 on the 2-step, RPM mode. Again, hooked with no hop and just a bit of spin.....enough to just chirp the tires. So, that's 6 passes with the Steeda bushing supports, sub frame braces and vertical links and the car is showing ZERO wheel hop. These last 3 were what I was really looking for as the car was hooking and showing no sign of hop at all.
Did you find this helpful?  1 of 1 Found Helpful
I'm officially a believer!
Ok. So I know everyone has already made threads about their Steeda stuff, but I'm officially a believer! Springs Sway bars Sway bar Billet Brackets Vertical Links Toe Arms Bump steer kit G-Track Brace IRS bushings MMR Camber Plates Performance wheel alignment The car is a go kart. Set the front sway bars to the center and rear to the lower settings, entry high speed turn is predictible, so much so I haven't learned the limits yet. The ass can be easily manuvered with throttle (Race mode/traction off). The body roll seems like it's gone (once the track wheels/tires come in I'll know for sure), it's unreal, I am in LOVE with the car now. This is the way it should've come from the factory for the PP cars. Really a learning curve, since now everything is souch more compossed. The IRS bushings and arms drastically changed the feel of the car on take off, the power actually goes to the tires (which I spin even easier now, even with camber still within factory specs.) There's not that feeling like the IRS wasn't properly fastened, it feels like it's built in to the body. Such a great mod. I'm ordering the IRS brackets as well, but I don't see how it can really improve further. It that good!! Steeda has my vote!
Did you find this helpful?  1 of 1 Found Helpful
Wheel hop was reduced by about 50-75%
I had the bushing kit put on. I'd say the wheel hop was reduced by about 50-75%. I then had the rear subframe support braces put on, and the wheel hop is just about completely gone. Awesome stuff.
Did you find this helpful?  1 of 1 Found Helpful
Definitely less wheel hop
Just installed mine, pretty easy to install. Definitely less wheel hop but still there. What do you suggest next? Brace or links?
Did you find this helpful?  1 of 1 Found Helpful
I am a Steeda believer
The car is a totally different handling car. Took the wife for a ride today and she said it is smoother than before. Much less bouncy. That is good news to me. Cause if the wife is happy I am happy. But I will say that these mods have really changed my confidence in the car. I had one little 30mile spirited section with S curves on my way home that normally when they say 45mph.. you can take them at 55mph... I took them at 70mph and the car was just planted solid. No roll, no rebound and no breaking loose on the rear when I accelerated from the apex. It just transitioned smoothly and predictably. Now the only thing the wife did notice was the gear whine. Yes the Red differential bushing will cause some gear whine, but I have been told that replacing the stock gear oil in the rear end will help quiet that noise down. We will see as I will most likely change mine out here in the next week. Amsoil or Royal Purple is what a lot of people recommended. So, all in all, if someone is on the fence about these suspension upgrades, just do it. The guys at Steeda are top notch and know their stuff. Almost all of them have Mustangs and the owner even races them. A final shout out to [email protected] What a great help he was. He made sure everything was ready and there, his recommendations were spot on. David, again, Thank you man. I can hardly wait for the next batch of Steeda goodies come out.. Count me in already. I am a Steeda believer.
Did you find this helpful?  1 of 1 Found Helpful
Steeda's components will go a long way
The good thing with most of these Steeda components, with the exception of the bushing supports, is that they can be retained if you do the solid bushings to further stiffen the subframe and stock suspension. Obviously the bushing supports wouldn't be used with the solid bushings, but the subframe supports, toe-links, and vertical links can, and SHOULD, be retained.
Did you find this helpful?  2 of 2 Found Helpful
There are no reviews for this product!

Related Items

123123 - 1
Back to TOP
0 Items