Ford 4L7Z-5K238-AA
Tail Pipe

Service and repair work on the dual converter Y-pipe must begin with the vehicle set to NEUTRAL position on a hoist. First disconnect heated oxygen and catalyst monitor sensors before removing and discarding the catalytic converter-to-exhaust manifold nuts and reducing the clamp tension. The LH converter requires extra care to protect the converter inlet flare and manifold outlet flare and converter studs as the part is separated and removed. Perform the following procedure for the RH converter: Discard both flag nuts and converter-to-muffler flange bolts before using a suitable jack stand to stabilize the muffler and removing its isolators. Then lower the muffler assembly. When extracting the bolt along with its accompanying isolator cap and RH converter you need to maintain safety by avoiding contact damage to the manifold outlet flare and converter inlet flare and studs. Workers should detach heated oxygen and catalyst monitor sensors from their position and apply anti-seize lubricant to the threads before reinstalling them. All fasteners must remain loose until vehicle assembly starts from the front side. Always install new fasteners and gaskets while performing cleaning operations on the inlet pipe and catalytic converter together with the manifold outlet flare and converter inlet flare mating surfaces. Reinstallation requires following the removal steps while adjusting the exhaust system to achieve its maximum operational space. First tighten the nuts starting with the RH lower catalytic converter-to-exhaust manifold followed by the RH upper catalytic converter-to-exhaust manifold and transmission mount hanger bolt then exhaust clamp nut and finally alternate tightness of the LH catalytic converter-to-exhaust manifold nuts enabling the LH inner nut to be snug before tightening the LH outer nut to specification and finishing with a specification-tightened LH inner nut. Conclude the process by securely tightening all catalytic converter-to-muffler bolts.