The best way to explain the installation process of the Lateral Dynamics 3 Link suspension setup is by showing pictures of an actual installation. The pictures that follow were taken during the installation of our customer, Jeff S. at our shop in Carlsbad. Rather than use a lift, exotic tools, etc, we used equipment that a typical serious hobbyist would either have, or have easy access to, such as an air compressor, MIG welder, reciprocating saw, hand tools, etc. Further, this entire installation was done by one person alone, and while it is easier in many steps to have a buddy helping out, the purpose was to show that it is not impossible to accomplish by yourself.

As with any episode that involves working on a car, please make certain to observe safety standards at all times, including eye and hearing protection, and pay attention to manufacturer’s instructions on the use of tools and equipment. Always work in a ventilated area, especially when welding, and be certain that fire protection is present in case of emergency. Remember, please: SAFETY FIRST.

The first step in the process is to inspect the car for any alignment or frame damage that will affect the installation of the new rear suspension. Measure the wheelbase and cross-wheel dimensions to insure the car is square and true. Disconnect the battery, drain and remove the fuel tank. At minimum, drain the rear portion of the brake hydraulic system, and remove the rear brake line leading to the axle assembly from the rear chassis area. Remove the back seat, it is also preferable to remove the front seats for easier access to the interior, and remove the carpeting and all sound insulation material from the floor.

Drop a plumb bob down the side of the quarter panel to establish the wheel/axle centerline, and mark this location on a piece of high quality masking tape placed on the quarter panel edge. This reference will be used later, so it is important that it will not move or fall off.

Set the car on a set of jackstands to gain clear access to the undercarriage. Lift both the front and rear of the car, and adjust so that the car is level to the ground.. Carefully remove the rear axle assembly, leaf springs, and all hardware.

The forward crossmember comes first. All applications will be a bit different, but there will be a reference point to key off of to insure the proper location. Because the crossmember will fit half above, and half below the stock floorpan, and also because the factory tolerances were typically not very tight, it is best to “sneak up” on the final cut by making a series of clearance cuts and repeated trial fitting. On the first gen F body cars, the first point of interference is the driveshaft tunnel where the UCA mount is. Make a trim cut here.

Mock the crossmember up, insuring it is level, and continue tracing cut lines and trimming.

Keep sneaking up on it.

A little more, and the crossmember can be placed in the final position.

After the sheetmetal is trimmed and the crossmember fits properly, it can be fully welded to the frame rails under the car.

Next, the rear crossmember can be fitted up. Here again, the exact method and placement will depend upon the specific vehicle type, on the first gen F body cars there is limited area behind the rear axle assembly, and as a result, a clearance cut will need to be made in the trunk area. After mocking up the crossmember, and clamping in place temporarily, the trim lines can be made, and the sheet metal trimmed.

Once the sheet metal is out of the way, trial fit the rear crossmember.

Before welding the rear crossmember in place, a trial fit of the new rear axle assembly is made to insure that everything fits as intended.

Once all critical measurements are verified, the rear crossmember can be fully welded into place. Next, it is time to make clearance cuts for the upper link, and to fit the sheetmetal closeout pieces necessary to isolate the interior of the car from the outside.

Starting with the trunk, a new “tray” is placed in the area behind the rear crossmember assembly.

Now we are ready to fit up the rear “box” to clear the Upper Control Arm Mount present on the top of the new rear axle assembly.

Now the attention shifts to the driveshaft tunnel area. A trim cut is made, and the factory sheetmetal is manipulated to fit the forward closeout panel.

After a bit more trial fitting and trimming, the pieces can be tack welded into place.

A bit of seam sealer will complete the installation of the new sheetmetal, and a coat of primer and paint will finish it off and protect it for years to come. Now the differential housing can be installed in the car, aligned, pinion angle set, and the installation will be complete. Jeff’s car is going directly to the body shop after it leaves our shop, and will be undergoing a full top to bottom, head to toe paint and refinish job. As such, we elected to powder coat all of the appropriate components during that time, rather than to do the work at this time.

The differential case, axles, and brake system were all trial fit, and the axle assembly was installed into the car. A quick alignment and pinion angle set was accomplished, and then the car made its way off to get a fresh body makeover. The rear suspension CERTAINLY looks a whole bunch different, and a lot better than it did when the car showed up!