stock driveshaft diameter

I measured the circumference of both driveshafts (11") and divided the numbers by pi (3.1415926) to get the diameter.

Well I just crawled under mine. The mid shaft circumference is 11 5/16" using a fabric tape. So, 11.3125"/3.1415926 = 3.6008806" diameter. I no longer have my OEM but I vividly recall it being significantly smaller.
 
It might be, im sure its hits the muffler, but it might be hitting both, i took the dog bone off and did not put the little plate back on, i dont know how it goes back on...does anyone have a pic of there pinon snunber and the dog bone plate????



The plate mounts above the differential and bolts into the flange on either side. IIRC the raised portion is offset but it should be obvious as to which way it sits when you look at where the snubber would make contact. Can't recall the bolt size but I do recall that you need a shorter length without the dogbone.