1998 Cobra T56 Viper Transmission Swap

The shifter area is much easier to access on '94-and-newer Mustangs. Grasp the edge of the shifter bezel and lift up to free its grip. Unscrew the shift knob and remove the knob and boot/bezel. Underneath this is the weather seal. Remove the four retaining bolts for the boot and slide the boot out of the way. If necessary, remove the shifter handle to prevent tearing the seal.

With the weather seal and shifter handle out of the way, the actual transmission and the shifter assembly are now visible. Remove the bolts retaining the shifter assembly and break the silicone seal to remove the shifter. This allows for more working room under the car when trying to slide the transmission back for removal.

The exhaust system will need to be partly removed for clearance. Unbolt the after-cat assemblies from the H- or X-pipe. Remove the nuts retaining the H- or X-pipe to the manifolds/headers and pull the H-/X-pipe out of the way. Don't forget to disconnect the oxygen sensors.

The driveshaft will need to come out to allow removal of the transmission. In addition, the shaft will need to be shortened or replaced for the conversion. To reduce the downtime for Editor Turner's Cobra, we opted for a direct-fit driveshaft from D&D. If you haven't drained the transmission fluid, you will lose some from the tailshaft area, so either first drain the transmission or have a plastic tailshaft shipping cap ready to seal the transmission upon shaft removal.

Since the crossmember is to be replaced with the modified piece sent with the D&D T56 kit (for our applica-tion), there's no need to unbolt the crossmember from the trans mount. Simply back out the crossmember-to-framerail retaining bolts until the retaining nuts on the bolts are free. Leave the bolts in temporarily to support the rear of the transmission.

The Tremec 3550 bolts to a bellhousing similar to that of a T5 with four bolts. Remove the four bolts from the transmission in preparation for its removal.