It's 3 stud and 2-1/2" inch It's a CC-300 GMC 1-1/2 ton with a 248 ....... no muffler shop for 200 miles. this is the OEM pipe. NAPA has like 200 exhaust pipes hanging like Christmas tree ornaments and sound like wind charms. I would just like to find someone that makes one for 41-46 GM truck/PU
