Porterbuilt Street Rods Dropmember

Install Article by Brad Walker

When most people start to lay out a 63-87 Chevy/GMC they quickly realize that the front cross-member hits the ground well before the frame. Typically people will either Z the frame or section the front cross-member. This involves a lot of work and can easily cause problems with the steering. However the guys at Porterbuilt Street Rods have come up with a solution. They have designed and perfected what they call the Dropmember. This kit is a total bolt on replacement for the stock front cross-member. However the Dropmember moves the suspension up out of the way of the tarmac. This kit not only raises the suspension mounting points, it also narrows the track width, and allows the owner to run a Mustang II rack and Pinion. The kit is designed to work with Air Ride Technologies Strong Arms, but with slight modifications the stock control arms will work. This kit bolts into existing holes and will allow your truck to lay frame on 29” tires with three-inch drop-spindles. Follow along as we install one on a 1969 Chevy C-10.

Step One: (below)
You will need to pull the motor to install the Dropmember. In our case we stripped the Truck down to the frame in preparation for more modifications.
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Step Two: (not pictured)
You will need to dismantle all the original steering components.
You will not be using any of this back.
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Step Three: (above)
Start to remove the original suspension and cross member. This can be done as one piece. We decide dto take the suspension apart then drop the cross member down. Be prepared, these bolts and nuts have been installed for 25+ years.


Step Four: (above and below)
You will need to install a notch in front of the Dropmember. This will give the Mustang II adequate clearance. You can cut this out using what ever you want. The provided notch will need to be welded into to place. It is located 4.25” from the front lower mounting hole of the dropmember.
Step Five: (right)

Next you will have to get out your ½” drill. You will need to open up several of the factory holes. At this point we also went ahead and sprayed all the bare metal pieces in an Etching Primer.


Step Six: (left)

After drilling out the original holes you can install the inner frame piece.

Step Seven: (right)

Next we installed the main section of the Dropmember. There are three ½” Grade 8 bolts that go in each side. It will take a little tweaking to get all the holes to line up. We used a pry bar to spread the frame rails the small amount we needed to get it to line up perfectly.


Step Eight: (left, below)
Now you can install the bag mount/upper control arm mount. You will have to drill one extra hole on each side. There are seven 7/16” Grade 8 bolts per side you will have to install and tighten on this piece alone.




Step Nine: (above, upper left, left)

Now you can install the lower control arms. The kit comes with a locator pin that needs to go into the cross-shaft and bottom of the mount. Then you sandwich the cross-shaft with the other mounting piece and use the ten 5/16” Allen head bolts. If you are using your stock lower control arms, you will have to trim a small amount off. If you are installing the Strong Arms you will have to drill new air bag mounting holes.



Step Nine - A (left)

In the picture you can see the small amount trimmed off of the lower control arm. We test fitted it several times so that we trimmed as little as possible.

Step Ten: (right)

Next we installed the airbag. The top of the bag installs to the Dropmember. A spring cup is mounted to the bottom of the bag. If you install the Strong Arms the bag will mount to the control arm.



Step Eleven: (left)

Next we installed the upper control arms using the supplied hardware.

Step Twelve: (right)

Before installing the spindle, it will need a slight modification. The steering arm will need to be drilled out the 5/8”. This allows the mounting the heavy duty Heim joint used on the Mustang II Rack . Once that is done you can install the spindle. After drilling out the steering arm install the drop spindle.

Step Thirteen: (not pictured)

With all this installed you can install the Mustang II Rack. The kit comes with aluminum bushings that you use to install the Dropmember. The kit includes and extension and a Heim for each side. This mounts to the rack and to the spindle.


Step Fourteen: (right)

The kit also comes with new motor mounts. Our kit came with mounts for a Small Block Chevy.


Final Note:

Once you get to this point you will need to install a new power steering pump or a pressure reducer. You will also have to get a few steering joints and a shaft. This kit also comes with a new transmission cross-member. The cab will have to be slightly modified as well, you will have to install a larger transmission hump.

Special Thanks:

Porterbuilt Street Rods
(480) 326-6303


The Draggin Lair
(615) 512-8301

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