'94-'97 Powerstroke 4" Exhaust Install
Start by removing the stock exhaust. You can remove it in one piece but it requires you to jack up the back of the truck by the frame not by the axle as far as you can and twist it out just right. You can unbolt all the hangers from the frame except the one being the rear tire which you will use and is riveted to the frame anyway.
Start by bending the hanger on the tail pipe toward the front of the pipe 1"-2". Trial fit the tail pipe until it lines up with the top of the hump being properly positioned over the axle.
If using a Hypermax or similar down pipe that has a 3.5"ID end use a reduce with a 3.5"OD on one end and a 4"ID on the other. If using a down pipe that bolts to the factory cat flange or doing a cat back system use a reducer with a 3.5"ID on one end and a 4"ID on the other.
It may be necessary to install a 15 degree elbow on some applications. If when the muffler and/or 4" pipe hits the bottom of the cab before it lines up with the tail pipe you will need to add this elbow. Cut factory pipe where the reducer is to be attached if necessary and install reducer.
Measure the distance between the tail pipe and the down pipe (or where ever you are attaching it at the front) and cut a piece of 4" pipe to the proper length. If using a muffler subtract the length of the muffler. When measuring make sure you measure to the inner lip of the slip joints or the pipe will be to short and when measuring the muffler make sure to subtract for the depth of the slip joints on both ends.
Tail Pipe to Reducer Length
Crew Cab without 15 degree coupler 88"
Using Jack Stands or something similar to hold the 4" pipe up install it into the reducer or 15 degree elbow at the front. Then install the muffler (if applicable) onto the 4" pipe and install the other end of the muffler onto the tail pipe. If you aren't using a muffler use a 4" band clamp to join the joint between the 4" straight pipe and the tail pipe.
Bend One hanger at 90 degrees at the top of the 4th hole as shown below.
Bend the other hanger flat at the pivot point as shown below.
Drill a hole in the frame cross member just in front of the rear tire on the 45 degree portion and attach hanger using a nut, bolt, and lock washer and attach hanger to 4" straight pipe as shown in picture.
Bolt the other hanger to the existing hole in the middle cross member and use a 4" clamp to attach it to the 4" straight pipe as shown.
If desired attach 45" bend to end of tail pipe using 4" clamp and position however you desire.
Pictures Of Other Options