Do we have stickies here? Someone needs to sticky this! Oh, and one correction - CCS stands for coast clutch solenoid. And some of my findings on its operation: in manual 1st and 2nd gear (select those with your shifter) the clutch is applied hydraulically, as in the solenoid is bypassed so you have engine braking no matter what the PCM's thoughts on the subject maybe. The coast clutch is also applied by the PCM when the trans goes into OD. When the transmission is in 3rd automatic the coast clutch is NOT applied by the PCM, which is why manually locking the converter then will not give you the engine braking you want. The PCM will apply the coast clutch when you manually select 3rd gear (use your OD cancel button on the dash or the shifter), so for good engine braking in 3rd you need to lock the converter and lockout the OD.