My Trac:
Gen1 Job2
2001 4X4
My OEM exhaust lasted up until 2012 before having to replace (not bad at all in my book). I installed it myself with Walker OEM replacement from new gasket at converter pipe flange to rear pipe exiting out to the side behind rear wheel all of which is 2 1/4". Again, it's time for a whole new exhaust system because the pipes and muffler rotted away.
The muffler is supposedly SS, which is bull, but they throw down so much salt in the winter where I live here in NY that it will eat through anything. Fortunately, I ordered the Walker muffler through Advance Auto and the idiots have a lifetime warranty on it so I'm bringing in the old one to have them give me a new one for the next time (in 3 years) when I have to replace it again.
Here are the part #'s:
36129 Spring Bolt Kit
31372 Pipe Flange Gasket/Seal
31962 Flange for Intermediate Pipe (to connect to converter pipe flange)
53460 Intermediate Pipe
21478 Muffler
55358 Rear Pipe w/Resonator (side discharge & wide brushed finish tip like OEM)
35336 2 Clamps 2 1/4"
I have the new exhaust parts sitting right here in my house. The muffler measures (w/caliper gauge) 2.38 - O.D. and 2.25 I.D. on BOTH sides. The muffler fits OVER the Intermediate Pipe (measuring 2.23 O.D.) coming into the muffler and OVER the resonator pipe (measuring 2.23 O.D.) going out of the muffler.
This time I had to buy a two piece flange for the end of the converter pipe because it has completely rotted and there's hardly nothing left to attach the new bolts. This is a two piece unit that you slip over the converter pipe end from both sides and bolt together. If anyone ever needs to do this it's also a Walker part that's available.
36131 Flange Repair Kit
I never measured my stock OEM pipe diameters when I removed it so I can't help you there but you should get yourself a cheap digital caliper gauge (in./mm) to have on hand for stuff like this. I paid $8.00 for mine at Harbor Freight and it works perfect for general measurement.