Common Transmission
Borg-Warner Model 66 automatic problems (early cars)
Symptoms
Harsh shifting, slipping, delayed engagement, overheating. The BW66 is simply not strong enough for sustained V12 power.
Cause
Under-engineered for the application. The BW66 was adequate in lighter, less powerful cars but struggles with the V12's torque and heat output.
Fix
If it's still working, service it (fluid and filter change, band adjustment) and hope.
If it fails, replace with a GM TH400, conversion kits are available.
Budget $3,000-5,000 AUD for the conversion.
Cost mentioned in fix
Budget $3,000-5,000
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