Transmission Parts

Browse all Sonnax transmission parts here, or use the filters below to find just what you are looking for.

Find a Distributor

View Sonnax Part Instructions

Enter a Sonnax part number below to view its instructions. For general reaming instructions, click here.

55-50SN, 55-51SN B5 Control Spring 59947-33

55-50SN • 55-51SN

B5 Control Spring 59947-33

Also fits AF23/33 and RE5F22A. Only some '05-later units were equipped with a control spring in the B5 clutch control valve lineup.

    Helps cure:
  • Incorrect valve body calibration
  • Missing B5 control spring
  • 2-3 Harsh
  • 3-2 Harsh
  • 2-3 Flare
  • 3-2 Flare
42RE, 42RH The Sure Cure® Kit SC-42RHE

42RE • 42RH

The Sure Cure® Kit SC-42RHE

    Helps cure:
  • Low cooler flow
  • Lube failures
  • Build up of release pressure during lockup
  • Converter bushing failure
  • Lockup shudder
  • Overheated converter
  • Soft TCC apply
4T60-E, 4T65-E 3-2 Manual Downshift Valve 84754-37K

4T60-E • 4T65-E

3-2 Manual Downshift Valve 84754-37K

Fits ’94-later 4T60-E. Does not fit 4T65-E Geartronic® or Tapshift® units.

    Helps cure:
  • Erratic shifts
  • 2-3 Shuttle
  • No 3rd
  • No 4th
  • 2nd Gear starts
  • Temperature-sensitive shifts
4L60 The Sure Cure® Kit SC-4L60

4L60

The Sure Cure® Kit SC-4L60

    Helps cure:
  • 3-4 Clutch failure
  • Burnt clutches & bands
  • Excess pump noise
  • Low line pressure
  • Low line rise
  • Low Reverse boost
  • 2-3 Shift feel poor
  • Early upshifts
  • Soft upshifts
  • Soft shifts
  • Slide shifts
  • Delayed Reverse
4T65-E The Sure Cure® Kit SC-4T65E

4T65-E

The Sure Cure® Kit SC-4T65E

Enclosed pump slide pivot pin does not fit late-style, 3-piece pump.

    Helps cure:
  • Low line rise
  • Low Reverse boost
  • Soft shifts
  • Maximum adapt
  • Long shifts
  • Converter shudder
  • Overheated converter
  • Code 741, 1811
  • Falls out of lockup when hot
  • No lockup
↑