In 1953, Ford slightly redesigned its F-series pickups and in the process revamped the names of the F-series trucks; the F-1, F-2 and F-3 became the F-100, F-250 and F-350, respectively. The 2006 Ford F-250 had three engines available, but it came standard with a 300-horsepower, 5.4-liter V-8 engine. This engine, as with all modern automotive engines in the U.S., came fitted with a catalytic converter, which converts harmful gases in the exhaust to harmless ones. Replacing the catalytic converter on the base level 2006 F-250 is a straightforward task
Instructions
1 Allow the vehicle to sit until the engine is cool to the touch, then allow it to sit for an additional hour to allow the catalytic converter to cool, as the converter typically is significantly hotter than the rest of the exhaust and retains heat more effectively.
2 Kick wheel chocks behind the rear wheels and raise the front of the F-250 with a floor jack. Slide jack stands under the frame rails and lower the vehicle onto the jack stands.
3 Crawl under the middle of the truck until you have a clear view of the catalytic converter.
4 Remove the four catalytic converter-to-Y-pipe nuts, using a ratchet and socket. If the nuts are seized, spray penetrating oil onto them and wait for the amount of time the oils instructions prescribe.
5 Loosen the clamp securing the intermediate pipe to the catalytic converter pipe using a ratchet and socket.
6 Trace the wiring for the catalyst monitor, the oxygen sensor on the catalytic converter, upward until you reach where its harness connects to the F-250s harness. Unplug the sensors harness from the F-250s harness.
7 Press the rubber catalytic converter hanger from the catalytic converters bracket. Press the converter rearward until the converter-to-Y-pipe studs are free from the Y-pipe, and lower the front part of the catalytic converter. Slide the catalytic converters pipe from the intermediate pipe and remove the converter from the truck.
8 Remove the catalyst monitor, the oxygen sensor on the catalytic converter, using a ratchet and oxygen sensor socket.
9 Apply a thin coating of an anti-seize compound to the catalyst monitors threads and hand-tighten the monitor into the new catalytic converter. Tighten the catalyst monitor to 34 foot-pounds using a torque wrench and oxygen sensor socket.
10 Scrub the mating surface on the Y-pipe with a wire brush. Guide a new catalytic converter-to-Y-pipe gasket onto the mating surface on the catalytic converter. Clean the mating surface on the inside of the intermediate pipe with emery cloth.
11 Lift the catalytic converter into place and press its bracket through the hole in the converters rubber hanger. Guide the convertor-to-Y-pipe studs through the bolt holes in the Y-pipe. Hand-tighten the four converter-to-Y-pipe nuts onto the studs.
12 Guide the rearmost pipe on the catalytic converter into the intermediate pipe. Move the intermediate pipe-to-catalytic converter pipe clamp so its within 0.15 inches of the end of the intermediate pipe and the bolt is at a 90-degree angle relative to the slots cut in the end of the pipe.
13 Tighten the convertor-to-Y-pipe nuts to 30 foot-pounds using a ratchet and socket, and tighten the intermediate pipe-to-catalytic converter pipe clamp to 41 foot-pounds.
