I'm just researching these as it seems I will need both.

What is the difference between the 15725 and 15735 oxygen sensors? Can I use either in a 1987 2.1L Vanagon.
Is there a preferred muffler brand? I see Bosal, Ansa, Dansk, Ernst and Walker. All seem to be around $125-$150. What else will I need to replace the cat and muffler? It looks like the muffler hangers cost as much as the muffler.
Do list members still get a slight discount from Bus Depot?
Thanks.

-David ('87 Wolfsburg)

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