Replacing your Fox Body Mustang’s K-member is an important step for many builds. A new K-member can help you shed weight and improve your handling. If you’re considering an engine swap you’ll also want to consider replacing your K-member.
Here’s what you should know about your Fox Body Mustang’s K-member and how you can select a new one that’s right for you.
What Is a K-Member?
A K-member is a type of crossmember. Like a crossmember, a K-member supports the engine and the suspension in the front of a vehicle. In a longitudinally mounted engine, like the one in your Fox Body, the K-member also contains the engine mounts.
The K-member is what the front control arms, steering rack, and the engine are all bolted to. The front suspension needs the K-member in order to transfer its loads to the unibody frame.
This makes the K-member one of the most important and least talked about pieces in your Mustang’s suspension.
Because it also supports the engine, the K-member and engine must be compatible. This means that K-member swaps are often a component of engine swaps.
Ford’s stock K-member was a two-point K-member. Many aftermarket K-members provide more points of contact for a stiffer suspension and better handling. Depending on your K-member selection, you can also see significant weight reduction.
What Makes a Good K-Member?
The K-member ties the entire front end of your Mustang together. You want a durable K-member that can easily withstand any suspension stress and support the engine’s weight. A rigid K-member is best for a solid handling experience. Finally, you want a light K-member, but weight savings need to be balanced with strength. A weak but light K-member is basically worthless.
One factor that will most impact durability, weight, cost, and rigidity is material. The material that a K-member is made out of is extremely important.
Chromoly is an alloy of chromium, steel, and molybdenum. It has an excellent strength to weight ratio, which makes it ideal for a K-member. Because it’s not as corrosion resistant as other materials, it will often be powder coated for additional protection.
HSLA steel stands for “high strength, low alloy.” Though still steel, these K-members can weigh more than 50% less than stock K-members.
Other K-members may be made out of steel, like the original K-member. Though they’re both made out of steel, the shape can affect both the weight and strength. Generally, tubular K-members will be both lighter and stronger.
K-members impact your suspension geometry. Depending on what K-member you select, you also may limit your suspension options. Many K-members only work with coilovers, or require aftermarket control arms to complement them.
If you’re especially focused on performance, suspension geometry is very important. Drag racers typically look for a K-member that pushes their front wheels forward slightly. This adds stability for harder launches.
For drift builds, tubular K-members are especially popular. These allow plenty of room for headers and other modifications. They’re also strong enough to handle the torque and steering angles of drift. Pay special attention to the strength of the mounting hardware and bushings.
One reason people select a new K-member is for an engine swap. Though some K-members have interchangeable engine mounts, you’ll want to make sure yours is compatible. This not only speaks to the engine mount location, but also to whether the K-member can support the engine’s weight.
Fox Body K-Members
Once you know what you’re looking for in a K-member, you’ll still have a lot of options.
Fox Body K-Member Braces
K-member braces are perfect for Fox Body owners who just need a little extra stiffness. These simple bars add strength to your existing K-member, reducing body roll and chassis flex. The only downside is that you don’t benefit from the weight savings of a new K-member. For those who are mostly happy with their Fox’s performance, this is a perfect compromise.
Fox Body Engine Swap K-Members
Fox Bodies were light, but lacked powerful engine options. This has made them popular for engine swaps. Coyote swaps are especially popular. Rather than trust your old stock K-member to support a brand new engine, check out these options.
Engine swaps are often part of a total performance rebuild. This makes extra features especially notable. Some K-members are designed specifically to work with coilovers, others help minimize bumpsteer issues.
Tubular Fox Body K-Members
Tubular Fox Body K-members are popular for several good reasons. These versatile K-members offer additional space for headers. They also tend to be lighter and stronger than the stock K-member.
Many tubular K-members are designed expressly for performance builds. These K-members will often include additional parts, like new control arms, that help improve the suspension for heavy wear.
Maximum Motorsports K-Member Kits
If you’re looking for a total performance suspension package, Maximum Motorsports has several options. These packages include:
- K-member brace
- Front lower control arms
- Bumpsteer kit
- Caster camber plates
- Steering rack bushings
- Sway bar end links
- Sway bar relocation kit
- Urethane sway bar bushings
- Coilover kit
It’s an entire front suspension package that takes the guesswork out of selecting compatible pieces.
Replacing a K-Member
Whether you’re doing a whole engine swap or just stiffening your suspension, swapping your K-member has obvious performance benefits. It’s an especially good mod for a Fox Body and is an important part of most performance builds.
Check out our full collection of K-members to find the perfect one for your Mustang.
This article was researched, written, edited, and reviewed following the steps outlined in our editorial process. Learn more about CJ's editorial standards and guidelines.