TIFFIN MOTORHOMES IS RECALLING CERTAIN MODEL YEAR 2011 ALLEGRO BUS AND PHAETON RECREATIONAL VEHICLES BUILT ON THE POWERGLIDE CHASSIS EQUIPPED WITH A CUMMINS ISX OR ISL DIESEL ENGINE. THE V-BAND CLAMP ASSEMBLY, PART NUMBERS Q187684, Q187685, AND Q187686, USED TO CONNECT THE INLET AND OUTLET CONE SECTIONS TO THE DIESEL OXIDATION CATALYST (DOC)/DIESEL PARTICULATE FILTER (DPF) INCLUDE A T-BOLT WHICH CAN FRACTURE AND FAIL WHEN SUBJECTED TO STRESS OR LOAD. A FRACTURE OR FAILURE OF THE T-BOLT MAY CAUSE THE CLAMP TO LOOSEN AND THE INLET OR OUTLET SECTIONS ATTACHED TO THE DOC/DPF HOUSING TO DISCONNECT.