If you're looking to change the profile of your S550 Mustang, adding a gt350r rear spoiler is probably the single best visual and performance mod you can do. It's one of those parts that completely changes the attitude of the car. When Ford released the GT350R, it wasn't just about the flat-plane crank engine or the carbon fiber wheels; it was about that massive, aggressive wing sitting on the trunk. It signaled to everyone that this wasn't just a cruiser—it was a track-ready beast.
Now, most of us aren't lucky enough to have a genuine Shelby sitting in the garage, but that doesn't mean we can't borrow a bit of that styling. Whether you're driving a 5.0 GT or a daily-driven EcoBoost, the "R-wing" look is something that just works. It fills out the back end of the car in a way the factory "lip" spoilers never could.
Why Everyone Wants the R-Wing Look
Let's be honest for a second. Most people want the gt350r rear spoiler because it looks incredible. The S550 chassis (2015-2023) has a very sleek, fastback design, but the rear can sometimes look a little "soft" from certain angles. Adding a tall, pedestal-style wing gives it that much-needed muscle.
There's something about the way the wing kicks up and out that balances the car's long hood. It makes the car look lower and wider, even if you haven't touched the suspension. It's also one of the few mods that people notice immediately. You can swap out your intake or your headers, and no one at a stoplight will know. But you bolt on this wing, and suddenly, you're getting thumbs-up from other enthusiasts everywhere you go.
Does It Actually Do Anything for Performance?
This is a common debate in the Mustang forums. Is a gt350r rear spoiler functional, or is it just "rice" for a domestic car? Well, if you're buying a high-quality replica or an OEM unit, it is absolutely functional.
On the actual GT350R, that wing is designed to provide significant downforce at high speeds. It helps keep the rear tires planted when you're taking a high-speed sweeper on a road course. Now, if you're just driving to the grocery store or cruising at 60 mph on the highway, you probably won't feel a difference. But if you do any track days or even "spirited" driving on backroads, that extra stability at the rear is a nice safety net.
The downside? Drag. A wing this big is going to catch some air. You might see a tiny dip in your top-end speed or a negligible change in fuel economy, but let's face it—if you're worried about 1 MPG, you probably shouldn't be driving a Mustang anyway.
OEM vs. Aftermarket: Choosing Your Spoiler
When you start shopping for a gt350r rear spoiler, you're going to find a massive range in prices. On one end, you have the genuine Ford Performance parts which can cost a small fortune. On the other end, you have eBay and Amazon replicas that are tempting because they're cheap.
Here is the deal: you usually get what you pay for.
- OEM/Ford Performance: These are the gold standard. The fitment is perfect, the finish is flawless, and the structural integrity is guaranteed. If you're building a serious track car, go this route.
- High-End Replicas: Brands like Anderson Composites or Steeda offer versions that are very close to the original. They often use high-quality materials like real carbon fiber or heavy-duty ABS plastic.
- Budget Replicas: These are great if you're on a budget and just want the look. However, be prepared for some "massaging" during the install. Sometimes the holes don't line up perfectly, or the finish needs a bit of sanding and a fresh coat of paint to look right.
The Installation Headache (and How to Avoid It)
I won't sugarcoat it—installing a gt350r rear spoiler can be a bit of a project, especially if your car came with a different style of spoiler from the factory.
If your Mustang has the "track pack" spoiler or the standard GT spoiler, you might find that some of the existing holes line up. But more often than not, the GT350R wing uses a different mounting pattern. This means you might have to drill new holes into your trunk lid.
If the idea of taking a power drill to your car makes you sweat, you're not alone. The key is to use a template. Most good aftermarket kits come with a paper template that you tape to the trunk. You mark your spots, center-punch them, and then—deep breath—drill.
Pro tip: Use some touch-up paint or a clear coat on the raw edges of the holes you drill to prevent rust down the road. Also, make sure you use the rubber gaskets or some silicone sealant. The last thing you want is a trunk full of water every time it rains because your spoiler isn't sealed correctly.
Carbon Fiber or Painted?
This is a big style choice. A lot of people love the look of a raw carbon fiber gt350r rear spoiler. It looks exotic, expensive, and fits that "race car" vibe perfectly. It looks especially good on lighter-colored cars like Oxford White or Iconic Silver because of the high contrast.
However, carbon fiber requires maintenance. If you leave it out in the sun all day, every day, the clear coat can eventually yellow or peel if it's not a high-quality UV-resistant resin. You'll want to keep it waxed or even ceramic coated to keep it looking fresh.
The other option is a painted finish. Most people go with Gloss Black, regardless of the car's color. Gloss black accents (wheels, mirrors, roof, and spoiler) are a classic Mustang look. It's easier to maintain and usually a bit cheaper than the carbon fiber versions. Plus, if you ever scratch it, it's much easier for a body shop to fix than a weave of carbon fiber.
What About the "Gurney Flap"?
You'll often see people talk about the "Gurney Flap" in relation to the gt350r rear spoiler. For those who don't know, this is a small, vertical lip that attaches to the trailing edge of the wing.
It's named after racing legend Dan Gurney, and its purpose is to further increase downforce without adding much drag. In the enthusiast world, adding a Gurney flap to your R-wing just adds another layer of "aggression." It makes the wing look even taller and more complex. It's a cheap add-on that really finishes the look if you're going for that full-on track aesthetic.
Maintaining That Aggressive Look
Once you've got your gt350r rear spoiler bolted on, you need to take care of it. Because it's a pedestal wing, it's going to catch a lot of dirt and road grime underneath it. When you're washing the car, make sure you get into those gaps between the wing and the trunk lid.
Also, be careful with automatic car washes—especially the ones with the big spinning brushes. Those brushes can put a lot of leverage on a tall wing like this. I've seen stories of wings getting cracked or even ripped off in those "scratch-o-matics." Hand washing is always the way to go if you want to keep your mods looking new.
Final Thoughts
At the end of the day, the gt350r rear spoiler is more than just a piece of plastic or carbon fiber. It's a statement. It tells people that you appreciate the heritage of the Shelby brand and that you want your car to stand out from the thousands of other Mustangs on the road.
Whether you're doing it for the aero benefits at the track or just so you can look back at your car in the parking lot and smile, it's a modification that rarely gets regretted. Just take your time with the install, choose the material that fits your lifestyle, and get ready for a lot of people to start asking you, "Hey, is that an R?"