TCM programing anticipates spring control response in the B5 control line-up in certain vehicles. Without this spring, the calibration is mismatched and 2-3/3-2 shift issues may occur.
The Sonnax B5 control spring is a direct replacement for the OE spring and it can be added to any valve body in order to match the TCM calibration.
Package Quantity: 5View Instructions
Only some Aisin AW 55-50SN transmissions ('05-later units installed in Nissan and GM vehicles) were equipped with a control spring in the B5 clutch control valve line-up. Using a valve body without a spring in those vehicles creates a mismatch between the B5 line-up and the TCM calibration, often causing a harsh 2-3 upshift or 3-2 downshift. Sonnax offers B5 control spring 59947-33 as a direct replacement for the OE spring. This allows rebuilders to rebuild any suitable core for use in vehicles where the spring is required, or correct shift concerns caused by a missing spring.