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Mustang Performance Parts

Steeda Mustang Rear Chassis X-Brace (05-14)

Steeda Mustang Rear Chassis X-Brace (05-14)
Our Price $279.95
Market Price $339.95  
You save $60.00 (18%)
280 points

Manufacturer:  Steeda Autosports

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  • Product Description
  • Installation Info
  • Mustang Fitment

Our latest rear chassis X-brace addresses the fact that not everyone wants to get rid of their rear seats for the added benefit of the rear chassis brace. Obtaining the rear seat delete parts from the Boss 302 can be an expensive task, and having a rear seat delete made can be a challenge as well.

After listening to these concerns from our customers, the result is our Steeda Rear Chassis X-brace that does not require a rear seat delete. This brace installs in the chassis area between the rear wheel wells behind the rear seats which effectively couples this part of the rear structure together to increase chassis rigidity.

Besides engineering the benefit of not having to get rid of the rear seats, this design is a significant improvement over Ford's original design for the Boss 302. Our X-brace mounts to the rear shock towers instead of attaching to the sheet metal behind the rear seats. This design is more effective and distributes the loads between the rear shocks, springs and the chassis, and not just the sheet metal of the vehicle. The result is much more effective chassis deflection reduction with improved suspension compliance over a sheet metal mount design.

This brace can be used as a bolt on installation or welded for maximum effectiveness.

Note: Does not fit convertibles or vehicles with Shaker/Mach 1000 stereo systems.

Product Benefits

  • Allows the rear seats to be retained!
  • Much more effective than other designs
  • Bolt on or weld on installation
Time to Install
About 1 Hour
Level of Difficulty
Tools Needed
Basic Tools
Model Year(s)
2014 2013 2012 2011 2010 2009 2008 2007 2006 2005

Bullitt GT V6 GT500 Boss

Manual Automatic

Product Reviews

Another GREAT part from Steeda. It really stiffens the car up, The suspension works SO much better, It feels like a different car with the X brace and the Torque Box/Frame rails stiffeners. People, Have this installed in you car, you won't be sorry.

Fits perfectly. I had it welded in for maximum performance and stability. So far had it installed for a week without any issues. The X-Brace does exactly how it should perform; stiffens the rear not on straights but on turns. It also helps with stability on bumpy roads creating a smoother ride and less interior noise.

I've had the best luck with chassis and frame stiffening. Each mod I've done has benefited both handling and ride compliance. The X brace is one of the best mods I've made. The interesting thing is, in addition to the improvement in ride compliance and handling that the steering has gotten lighter in a good way. Steering response has improved and I believe the "lightness" is possibly because the steering rack is not "fighting" chassis flex, it's more direct to the wheels now. Also, I have an aftermarket sunroof installed that had an occasional small creak going over curbs and now that small creak is gone, again probably due to decreased body twisting over curbs. Greet mod, should be first on the list for those who want to improve chassis rigidity. Also, it's great to still have the back seat. I have a 2014 pony package v6

I have had this brace in my garage almost a year, dreading to install it because I am not little, and I knew I had to crawl in that little trunk of my 2012 Boss.
I am sorry I put it off, it really wasn't that bad. I'll tell you if you have Coilovers (I have Penske Double adjustable) you have to reinforce the rear chock towers.
It's a different car.... unbelievable. It may be my imagination but it even shifts better.

This was the cherry on top of the sundae! Super easy install. I decided not to cut the side-carpet, but instead just rolled it inward.

Nice touch receiving a thank you card, too!

Great fit and finish. Excellent bang for the buck! Was pretty straight forward to install. The directions were good. I can't wait to see how this effects the handling on the track!

Awesome, genius product! It really stiffens up the chassis and lets you retain your rear seats!

What a great idea!! Add an x brace and keep the rear seats!! Yes please! Great price for the convenience of keeping your rear seats. Oh yeah and the handling is great!lol

I have a lot of Steeda suspension parts on my car and this just tops it all off. I feel like it completed my handling project. The shipment came fast and when I opened it up it was beautifully designed. Thanks for an awesome product!

Nothing but good things to say about this X-brace. Great quality, installed easily, and I can definitely feel the handling improvement. Plus, it was a great place to mount my custom stereo amps!!! Lastly, great customer service.