I have been noticing lately that with my converter locked either by the computer or with my lock-up switch. I get a bad shudder if I let the rpm's go down just a little. If I unlock it or downshift the shudder goes away. I also noticed last week that if I hit my lockup switch at idle with the truck in drive but at a stop it will no longer kill the truck. Usually if I forget to unlock it coming to a stoplight it would either bog the motor down fast or kill the motor. The converter is a dunrite triple disk close to 4 years old. I am thinking the clutch disks are warn or going bad correct?? Been about a month since last band adjust and fluid change. Any ideas ???