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  • Bang shifts
  • Flare shifts
  • Harsh Forward
  • Harsh Reverse
  • Harsh TCC apply
  • No lockup
  • Shift concerns
  • Soft upshifts


Internal component wear and sticking of the solenoid pintle cause critical SLT (line pressure) SLS (shift control pressure) and SLU (lock-up control flow) leaks and pressure concerns and spikes.


Replace faulty OE and aftermarket solenoids with the 100% tested and calibrated Sonnax remanufactured solenoids to eliminate sticking solenoid complaints.


Ensure correct style (early/short, early/long or late) of SLS/SLT solenoid based on connector direction and bracket design (Figure 1).

55-50SN, 55-51SN

Remanufactured Linear Solenoid Kit
Part No. 59947-70K


View Instructions

Aisin AW 55-50SN, 55-51SN, AF23/33 and RE5F22A linear solenoids are used to control line rise (SLT), the converter clutch (SLU) and the oil flow rate and accumulation for the clutch circuits (SLS). The flow-to and function of these solenoids overlap, making diagnosis difficult. The solenoids are prone to sticking of the internal pintle, creating inconsistent movement of the solenoid valves. Shift complaints and pressure/flow related issues result. Remanufactured linear solenoid kit 59947-70K was developed with an exclusive Sonnax process that eliminates sticking solenoid problems. These solenoids are 100% leak tested and calibrated to OE specifications. Readjustment should not be required if the valve body leakage has been addressed and a relearn process completed.

  • Eliminates pintle sticking problem for proper solenoid valve action
  • 100% tested and calibrated
  • SLS Solenoid, Green
  • SLT Solenoid, Blue
  • SLU Solenoid, Black

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  • 59947 70k
  • 59947 70k details

Sonnax Remanufactured Solenoids

Tired of the hit and miss swapping out solenoids from cores or the expense of just going with new? Sonnax remanufactured solenoids go through extensive disassembly and rebuild steps followed by rigorous inspection and testing. Top quality replacement parts and enhanced quality assembly and verification techniques ensure OE level operation for smooth, consistent shifting and extended service life. We have the hot models you need every day and what’s more, we are looking for your cores.