Adding Strut Tower Braces (STBs) to an LS4 W-Body

Special Thanks!

Special Thanks to Don Rome (RedHotG8) for modifying and packaging these awesome Strut Tower Braces (STBs) with his custom-made aluminum brackets and for helping to supply the niche market of performance parts for LS4 W-Body GM cars.

Special Thanks to 06montess for his telling me about this project and his help, both in the actual car work and the reviewing and editing of content. Thanks, man!


Just so you know, I'm not responsible for any inaccurate information, bad advice, or stupid puns which may or may not be present in this document. I'm not responsible for anything that may happen to your car as a result of doing anything, especially anything which may be described here. I'm responsible for mowing my lawn and that's about it.


General Motors designed the chassis on GM LS4 W-body cars (2006+ Chevrolet Impala SS, Chevrolet Monte Carlo SS, Pontiac Grand Prix GXP, Buick Lacrosse Super). They wanted to give the passengers a nice, smooth ride without feeling every bump in the road; to accomplish this, these cars have some amount of play and compliance such that as the car flexes, the body acts as a spring to absorb some of that energy. Unfortunately, as the car flexes, energy is lost and, more importantly, the angle of the wheels relative to the ground when viewed from the front (i.e. camber) changes. When the camber changes, the four small patches of contact between the tures and the road change shape and size and traction is lost.

To combat camber change during lateral acceleration, one can stiffen the vehicle through additional bracing; in particular, attaching the left and right side suspension components together (in the case of this suspension, the struts) with a rigid brace dampens the car's flexing and reduces compliance. This is what Strut Tower Braces (STBs) do. Check out the Strut_Tower_Brace page on Wikipedia for more information.

Fortunately, Don Rome (RedHotG8 on has designed and fabricated functional Strut Tower Braces which improve handling. These braces represent my personal favorite suspension / handling upgrade to date. Don's bars work great and look great; because the car handles better, it's also safer to drive.

You can find Don Rome's Strut Tower Braces (STBs) for sale on:

This project took about 45 minutes to complete with a basic set of tools.

What you need

You'll need several tools:

  • 1x 13mm socket
  • 1x 16mm deep socket
  • ratchet
  • torque wrench
  • hack saw or rotary tool (Dremmel) with cutting disk


Remove the inner two nuts securing the rear struts

I started by using my 16mm deep socket and ratchet to remove the two 16mm nuts that are closest to the center of the vehicle. The rear struts are above the rear wheels which, as you'll notice, is, basically, in the trunk. I found it quite challenging to access the rear struts from the trunk; instead, I lowered my rear seats and accessed the struts from inside the car.

I worked one at a time and removed the two 16mm nuts on one strut and then placed the the aluminum brackets over the (now) exposed bolts; the brackets are shaped such that the threaded holes for attaching the STBs go towards the center of the vehicle (rather than to the back). I then resecured the nuts. The nuts need to be torqued to 35 foot-pounds; the aluminum brackets are soft (well, I wouldn't want to get hit in the teeth with one..) so you'll want to use a torque wrench so as to not over-tighten the nuts. Once I finished one side, I moved to the other.

As a side note, there were two rubber caps on the tops of my rear struts but no caps on the tops of the front struts. There was no rust on the rear strut tops but there was a little on the front strut tops, so I took the rubber caps off of the rear struts and placed them over the front struts.

Driver's rear strut top with bracket installed
Passenger's rear strut top with bracket installed
Passenger's rear strut top with bracket installed

Attach the rear STB to the brackets on top of the rear struts

Next, I attached the rear STB to the aluminum brackets. The front STB has a notch in order to clear the alternator; the rear STB does not have this notch. I used a 13mm socket to tighten the supplied bolts to the brackets. Because, again, the aluminum is soft, you'll want to use the supplied washers between the steel (hard) bolts and the aluminum (soft) brackets. The threads on the aluminum bracket may strip if you over-tighten them, so you'll want to use the torque wrench to tighen to 10 foot-pounds of torque.

Driver's rear STB installed
Passenger's rear STB installed

Remove the two nuts securing the front struts

Climb out of the trunk--you're done in back!

Next, you'll want to remove the two nuts securing the front struts. Again, these are the two nuts closest to the center of the vehicle.

Once the nuts are removed, you'll notice that each of the front struts has a small threaded rod to which wiring clips are attached. These can be safely removed. I used a rotary tool (Dremmel) to buzz them off although you could probably use a small hacksaw just as well. If you don't remove them, then you'll most likely try to force the brackets into place and fail, possibly even getting online and asking your buddy for advice..

Driver's front strut top with nuts removed
Passenger's front strut top with nuts removed
Passenger's front strut top: notice the wire clip
Passenger's strut top with wire clip trimmed off

Install the aluminum brackets to the front struts

The procedure for installing the front aluminum brackets is the same as the rear aluminum brackets with the only difference being the shape of the brackets. Unlike the rear brackets which need to be mounted in a specific direction, the front brackets can be installed in either direction. Again, like in the rear, torque the nuts to 35 foot-pounds.

Passenger's front bracket in place

Install the front STB to the brackets on top of the front struts

Like with the brackets, installing the STB is the same in the front as it was in the back. The only difference is time is that there is an indentation in the front STB which provides clearance for the alternator, so make sure you have the STB oriented properly. Again, be careful not to strip the soft aluminum threads on the brackets by using a torque wrench to tighten the 13mm bolts to 10 foot-pounds of torque.

For what it's worth, should you lose a bolt, you can pick them up at your local hardware store--they're 5/16-18 x 1/2" and you'll probably want to go stainless.

Passenger's front STB
Driver's front STB
Front STB: Notice indentation for alternator clearance
Front STB: All braces in place

The finished project with painted engine cover in place

Go gentle on it until you're sure everything is seated properly and securely. You'll notice a slightly firmer feel the the ride, especially in corners. Where I really noticed the difference was when going around turns at speed. One turn near my house has a sufficiently small constant radius turn (a highway entrance ramp) that I would, formerly, slow to 20..25mph and then put the hammer down upon exit. The car used to feel like it might let go and slide if I went much faster. With the STBs in place, I shot around that turn at 45..50mph and tickled the gas and I was up to speed. The car felt like it was on rails and I didn't experience any sliding at all.

I do notice, however, some bumps can upset the feel slightly, especially when they're only experienced by one wheel. Since the left and right sides are now tied together by the STBs, a bump upsetting one wheel will affect the other side as well. Such is the price paid for a more rigid chassis.

I hope this helps! Please direct comments to Wes -at- LS4Store -dot- com.

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