This is one of those Fox body traditions just like the TPS 0.99v myth that simply won't die:
Many claim that with aftermarket suspension components, quad shocks aren't necessary. The truth of the matter is that this is a blanket statement that won't apply in every situation. Therefore, if there is no reason to remove the quad shocks (larger tires for example), then why do it?
Lets discuss what the quad shocks do. Ford has to meet certain NVH requirements on their passenger vehicles. Nobody would buy a new Fox Mustang that rode like a dump truck when brand new, so there was a certain level of compliance in the suspension bushings that was necessary to make the ride bearable. As a result of this compliance in the bushings, the rear axle could move/rotate slightly under load. During hard acceleration, the axle would move forwards and backwards on each side, creating what is known as wheel hop. The quad shocks were Ford's way of slowing the movements down with a pair of horizontal dampeners.
So, install some control arms that limit horizontal/rotational movement and solve the problem right? Not exactly. Not all control arms are the same. Some offer spherical bushings that allow ZERO horizontal/rotational movement, but cause the vehicle to ride like a truck (because: race car). While other control arms do over more compliant bushings made of rubber or poly of varying durometer ratings to retain some level of ride comfort, which may allow for some axle movement.
Long story short, the ability to remove your quad shocks isn't going to solely depend on installing aftermarket control arms, but depends on the compliance of the control arms you install. Not all are created equally. My own combo of Max motorsports HD control arms, with steeda uppers did in fact product wheel hop, until I reinstalled my quad shocks. Someone building a street/strip car may install different arms with spherical bushings at all location and may not need quad shocks at all.
On a street car, it's best to just leave them alone. If you need clearance for tires, try flipping them around first. But at least put in the effort to retain them....and please don't be so quick to suggest that everyone can just ditch them with aftermarket arms
As for cost of new quads, they are pretty cheap. Gabriel 14309 quad shocks can be had for around $20 each. If you need new hardware, they are listed as below.
Quad shock axle housing mounting bolts(12mm x 1.75 x 70mm)
New Gabriel quads installed on my car with MM control arms
Edit: just to add, pinion angle has been checked and is within spec. While improper pinion angle is proven to cause wheel hop due to axle windup, this post assumes this has been checked and it is within spec. In my case, my pinion angle is good.
Many claim that with aftermarket suspension components, quad shocks aren't necessary. The truth of the matter is that this is a blanket statement that won't apply in every situation. Therefore, if there is no reason to remove the quad shocks (larger tires for example), then why do it?
Lets discuss what the quad shocks do. Ford has to meet certain NVH requirements on their passenger vehicles. Nobody would buy a new Fox Mustang that rode like a dump truck when brand new, so there was a certain level of compliance in the suspension bushings that was necessary to make the ride bearable. As a result of this compliance in the bushings, the rear axle could move/rotate slightly under load. During hard acceleration, the axle would move forwards and backwards on each side, creating what is known as wheel hop. The quad shocks were Ford's way of slowing the movements down with a pair of horizontal dampeners.
So, install some control arms that limit horizontal/rotational movement and solve the problem right? Not exactly. Not all control arms are the same. Some offer spherical bushings that allow ZERO horizontal/rotational movement, but cause the vehicle to ride like a truck (because: race car). While other control arms do over more compliant bushings made of rubber or poly of varying durometer ratings to retain some level of ride comfort, which may allow for some axle movement.
Long story short, the ability to remove your quad shocks isn't going to solely depend on installing aftermarket control arms, but depends on the compliance of the control arms you install. Not all are created equally. My own combo of Max motorsports HD control arms, with steeda uppers did in fact product wheel hop, until I reinstalled my quad shocks. Someone building a street/strip car may install different arms with spherical bushings at all location and may not need quad shocks at all.
On a street car, it's best to just leave them alone. If you need clearance for tires, try flipping them around first. But at least put in the effort to retain them....and please don't be so quick to suggest that everyone can just ditch them with aftermarket arms
As for cost of new quads, they are pretty cheap. Gabriel 14309 quad shocks can be had for around $20 each. If you need new hardware, they are listed as below.
Quad shock axle housing mounting bolts(12mm x 1.75 x 70mm)
New Gabriel quads installed on my car with MM control arms
Edit: just to add, pinion angle has been checked and is within spec. While improper pinion angle is proven to cause wheel hop due to axle windup, this post assumes this has been checked and it is within spec. In my case, my pinion angle is good.
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