Ford Windstar Rail Replacement

This Research Bulletin covers complete replacement of the front unirail on a 1995-97 Ford Windstar minivan. Tech-Cor Research has received numerous inquiries regarding section procedures for this particular vehicle platform. As a direct result of documented offset crash testing and an in-depth evaluation, it was determined that collision damage resulting in extensive distortion to the rail kick-up area requires full rail replacement. This portion of the unirail contains an external reinforcement that also incorporates the rear cradle mount.

Although this bulletin focuses on replacement of the driver side unirail, the same procedure applies to the passenger side rail as well. Prior to removal of any structural components, the vehicle must be pulled and aligned to return the structure to its proper dimensions. The drivetrain assembly must also be removed to gain proper access for spot weld removal and subsequent plug welding operations.

During disassembly operations an additional inspection of the wiring harness should be made in the area immediately in front of the battery. During left frontal impacts, a flange on the radiator support baffle can be pushed rearward, cutting into the wiring harness at this location.

If wire damage is present, refer to Tech-Cor Information Bulleting 1995-4, Repairing Collision Damaged Wiring for proper repair procedures.

The two-piece unirail on this vehicle platform incorporates and "C" channel and separate closure panel.

There are several hidden spot welds securing the front floor plan crossmember to the "C" channel of the rail. This crossmember is located directly behind the drivetrain assembly, adjacent to the rear cradle mounting points in the immediate vicinity of the external reinforcement.

There is an additional crossmember located at the rear portion of the rail secured by six spot welds, two of which are hidden.

To gain access to the hidden spot welds in the front crossmember area, portions of the closure panel must be removed. This creates a window that permits working room for spot weld removal. When drilling the spot welds, drill only through the inner rail ("C" channel) and not into the hidden flanges.

At the rear crossmember, six spot welds need to be drilled.

NOTE: The drilled out spot weld locations must be accurately transferred from the damaged rail to the replacement "C" channel. These locations need to be drilled through.

All remaining spot welds that attach the damaged rail assembly to the body structure must also be removed. Photographs above and below show the hidden flanges on the front and rear crossmembers after the "C" channel is removed.

Prior to installing the replacement "C" channel, measurements should be taken from the original rail to determine the number and placement of spot welds that secured the "C" channel to the closure panel in the toe pan / floor area. These measurements are then transferred to the floor of the vehicle so that the holes can be drilled through both the floor and the "C" channel flange from the interior of the vehicle.

The replacement rail must be installed by first welding the "C" channel to the vehicle structure. After the "C" channel is installed, holes should be drilled through both the floor and "C" channel as indicated by the circles marked with an X. The "C" channel must also be drilled through at the existing spot weld holes in the floor to accommodate welding of the closure panel (indicated by area outlined in yellow).

This procedure will enable plug welding of the closure panel from the interior of the vehicle, rather than welding from underneath. This will also duplicate the number of original welds, as well as tying the floor pan to both the "C" channel and closure panel. All welding of the floor crossmembers to the "C" channel should be completed prior to installation of the closure panel.

NOTE: Corrosion protection, including the refinishing of replacement components should be performed as outlined in Tech-Cor Bulleting 1986-7, Restoring Corrosion Protection During Vehicle Repair.

Welding Information

Prior to any welding operations, the weld site must be cleaned to remove grease and dirt as well as primers and paint, without removing factory corrosion protective coatings or grinding into the base metal. Do not remove any pre-existing galvanized coatings. Do not use an oxyfuel (oxyacetylene) gas torch.

After cleaning, a weld-through coating must be applied to all bare metal in the overlap area of the weld sites. All welding should be performed with a M.I.G. welder (Metal Inert Gas, now called G.M.A.W. or Gas Metal Arc Welding).

Welding wire should be either 0.023/0.025 inch (0.6 mm) diameter which meets or exceeds the American Welding Society Standard (WAS-E-70S-6) with a mixture of 75% argon and 25% carbon dioxide shielding gas.

Do not concentrate all welding efforts on one area, but alternate sites so that each welded area has time to cool down before the welding is continued. All continuous welds must be made in 13 - 19 mm (1/2 - 3/4 inch) increments which helps to minimize heat build up which can cause metal strength loss and panel distortion. The welding equipment must also be properly adjusted by making and testing practice welds on similar materials.

The information provided in this bulletin is for educational purposes only. Although every effort has been made to ensure the accuracy of the information contained in this bulletin, Tech-Cor assumes no responsibility or liability for any repairs performed using information from any publication issued by Tech-Cor.

Any person performing repairs must determine whether any suggested or recommended procedures or repairs are suitable or appropriate for the particular vehicle being repaired. The repairer remains solely responsible for such determination, as well as for the proper completion of the repairs.

Reproduction of this bulletin is not permitted without the written approval of Tech-Cor.