These instructions can be used to install the shifter gasket on a 2004-2006 GTO. They are shown for the Billet Products shifter, but apply to any GTO manual shifter. They were compiled by Chris Butigieg.
Installation Vehicle: 2006 GTO, T-56 transmission, Billet Products shifter
Installation Time: 1.5 - 2 hours
Tools & Supplies Needed:
• Ramps or car jack with jack stands
•
• 3/8" drive ratchet extension
• 3/8" drive universal joint
• 16mm socket
• 13mm deep socket
• 10mm socket
• 13mm ratcheting wrench
• T25 Torx bit driver
• 5mm Allen head socket
• 6mm Allen head socket
• 6mm hex key
• 2.5mm hex key
• Pliers
• Phillips #2 screwdriver
• Common flathead screwdriver
• Razor blade
• 3M red scuff pad or similar
• Blue Threadlocker (required)
• Brake cleaner or degreaser
• Rags
• Black silicone adhesive or Skilaflex for shifter knob (your particular shifter may not require this)
Photo of the GTO T-56 Stang Shifter
Gasket shifter gaskets (base & handle).
Installation
Procedures
1. Drive car up on ramps. If you need more clearance, raise the
car with a jack and use jack stands for safety.
2. Use a No. 2 Phillips head screwdriver to remove the screw underneath
the head unit.
3. With your fingertips, pull plastic center console trim from the back
and move forward.
4. Work forward and upward. You will hear clips snapping while you're pulling up on the trim.
5. Remove power window and traction control connectors by pressing the
tabs and pulling the connector downward.
6. Pull trim piece back and up, making certain that you clear the two
lips up front (represented by the arrows).
7. Lift up on leather boot.
8. Use a flat head screwdriver to pry the clips away from the metal
handle while pulling the shifter knob with all your force since the knob is
RTV'd on the shaft from the factory.
9. Remove the foam piece.
10. Use a 10mm socket and ratchet to remove the indicated bolts.
11. Remove the two bolts as seen above.
12. Use pliers to remove the two harness clips along the base of the dust boot.
13. Use a jack to support the transmission, as you will be lowering the transmission a couple of inches to enable you to remove one of the four shifter bolts that has limited working clearance.
14. Transmission supported as seen above. Make a scribe mark on each side
of the bracket to ensure proper alignment when the transmission is bolted
back up.
15. Use a 16mm socket and ratchet to remove the 4 transmission brace bolts. Then use the jack supporting the transmission to lower it 2-3 inches.
16. Use a combination of ratchet extensions, Universal joints, and
wrenches to remove the four 13mm shiny nuts that secure the dust boot down
to the chassis.
17. Top view of the nuts location. Once the nuts are removed, pull the
dust cover off the shifter.
18. Remove the black dust cover (not used on Billet Products shifter).
19. Use a T-25 Torx driver to remove the four screws that hold the hard plastic dust cover (not used on Billet Products shifter).
20. With a 6mm Allen wrench and Allen head socket, remove and discard the
four bolts that secure the shifter base to the transmission. Retain the four
bolts if you are only installing the Stang Shifter Gaskets shifter gasket
and are not installing a new shifter.
21. To reach the back Allen bolts, use an L-shape Allen as shown in the illustration above or a hex head ratchet with a 6mm Allen head socket. NOTE: If the transmission is lowered enough, a flex head ratchet will fit.
22. Pull stock shifter out.
23. Clean mating surface with a razor blade or steel wool to ensure there is no debris left. Be sure no debris falls inside reservoir. Lay down a rag to catch debris if necessary. Finish the surface prep by using the 3M scuff pad.
24. Lay your Stang Shifter Gaskets base gasket on the area outlined in red in the photo above.
25. Lay the shifter directly in line with the holes it needs to be
screwed into. Do not move the shifter around much so that the base gasket
doesn't move out of alignment.
26. Apply Blue Threadlocker to the four bolts pictured above that hold the shifter down to the transmission.
27. Use a flex head ratchet with a 6mm Allen head socket to tighten all four bolts equally.
28. Use a longer 6mm Allen to reach the hard to get to bolt as shown
above.
30. Using a 2.5mm Allen, loosen up front bracket screws.
31. Using a 2.5mm Allen, loosen up rear bracket screws.
32. Crank up the motor, and with the clutch in, engage 3rd gear and adjust bracket until it is up against the shaft.
33. Tighten the 2.5mm Allen screws (Blue Threadlocker is recommended on screws.)
34. With clutch in, engage 4th gear and adjust bracket until it is up against the shaft.
35. Tighten the 2.5mm Allen screws (Blue Threadlocker is recommended on screws.)
36. Place the two dust covers over the shifter.

37. Install the shifter handle to your desired height. Apply Blue Threadlocker to the screws and tighten to shifter assembly with a 5mm Allen hex socket. NOTE: Steps 36 & 39 may differ, depending on the brand shifter you are installing.
38. Install the rubber dust cover along with bracket and tighten the 13mm
shiny bolts underneath. Drop the transmission a couple of inches again if
necessary. However, this is not required.
39. Install foam piece.
40. Depending on your shifter brand, apply a decent amount of black
silicone sealer adhesive or Skilflex on the shifter handle and install the
knob in place. If you apply too much adhesive the knob will not lock into
place. This procedure will secondarily help prevent noise emitted from the
transmission to the knob and into the cabin. DO NOT use RTV for this step!
41. Install all trim pieces back in place.
42. Connect traction control and power window connectors.
43. Drive vehicle off ramps or lower the vehicle to the ground.
44. Test drive the vehicle to ensure proper operation of all gears.
Please note that your new shifter may be initially stiff when you
shift gears, due to the higher quality springs used compared to the factory
shifter. This is normal. The springs will loosen up with 100-200 miles of
driving.