Warning: SLP recommends allowing the vehicle to cool (not running) for five hours before beginning the installation. SLP recommends wearing safety glasses for the complete installation.
Warning: Too avoid the chance of electrical shock or damage to your vehicle's electrical system, disconnect both the negative and positive battery leads (in that order) at the battery.
1. Raise the vehicle to allow for a sufficient work area underneath the vehicle. A vehicle lift will make this installation much easier, however, raising the vehicle can be accomplished using ramps or a jack with jack stands.
2. Disconnect the tailpipe and muffler assembly by unbolting the 2 flanges from the H-pipe and removing the exhaust hangers from the rubber insulators. If you are retaining your old tailpipes and mufflers you can just move them out of the way to allow enough clearance for removal of the old h-pipe and installation of the new x-pipe.
Note: If you are removing the original tailpipes and mufflers you may need to cut the old pipes in the vicinity of the rear axle or disconnect the shocks to gain enough suspension clearance to remove them.
3. Disconnect the wires from all the oxygen sensors.
4. Remove the nuts from the exhaust manifold to h-pipe studs and remove the original h-pipe assembly.* Save the original manifold nuts, as you will need to reuse them.**
*96-98 VEHICLES: You will need to unbolt the additional hanger from the transmission cross member prior to removing the h-pipe. You can discard this hanger, as you will not be reusing it.
**99-04 vehicles: Remove the studs from the driver side exhaust manifold because you will be replacing them with the M1 0-1.5 x 30mm bolts.
5. You may want to remove the oxygen sensors from your old h-pipe and install them in your new system now while access to them is easier. Be sure to reinstall the sensors in the same locations as in the original h-pipe.
Note: On 1999 vehicles there is an additional bracket on the transmission mount that the oxygen sensor wire harness attaches to. This bracket may interfere with the oxygen sensors on the SLP x-pipe. You may either trim this bracket to obtain the necessary clearance or simply remove it. Removal can be accomplished fairly easily by first supporting the transmission with a jack. Then simply remove the four bolts retaining the transmission cross member and mount to the floor followed by the 2 bolts retaining it to the transmission itself. Lower the cross member and mount, remove the bracket, and reinstall the cross member and mount in the reverse procedure. Whether you decide to trim the bracket or remove it you must make sure the wire harness is clear of any exhaust parts when the installation is complete. Using tie wraps to secure the harness to the cross member is a good idea.
6. Place the Driver Side Head Pipe onto the driver side exhaust manifold outlet. On 96-98 vehicles slide the flange onto the manifold studs and thread the nuts into the studs. On 99-04 vehicles insert the two M1 0-1.5 x 30mm bolts through the flange and thread them into the exhaust manifold. Leave the nuts/bolts loose enough to allow for later adjustment.
7. If it has not already been removed then remove the old passenger side exhaust manifold gasket from the manifold flange and place the new gasket onto the flange. Tabs on the gasket should hold it in place on the studs.