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  • Low line pressure
  • No 3rd & 4th
  • 2-3 Flare
  • Delayed Forward
  • No lockup


Bore wear from continuous oscillation of the solenoid modulator valve causes shift- and converter-related problems.


Oversize the bore and install the replacement valve kit to re-establish proper modulated solenoid pressure.


Oversized Solenoid Modulator Valve Kit
Part No. 94987-14K

This kit fits '98-later models: Isuzu NPR, GMC Forward Tiltmaster, Chevrolet Forward, Nissan UD and Mitsubishi Fuso Trucks.

You need this if... View Instructions

Aisin AW 450-43LE transmissions may exhibit multiple shift problems due to excessive wear in the solenoid modulator circuit. Loss of 3rd, 4th gear and no TCC apply are common, along with low line pressure and flare shifts. Bore wear at the inboard end results in high solenoid pressure, improper gear or harsh shifts. Oversized Sonnax solenoid modulator valve kit 94987-14K allows the bore to be renewed, restoring hydraulic integrity for a properly modulated solenoid pressure.

  • Valve is hardcoat anodized to reduce wear
  • Valve has added length at the outboard spool for additional support
  • Valve
  • Spring
  • End Plug

Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.

Aisin AW 450-43LE Valve Body Layout

Aisin aw 450 43le
  • 94987 14k combo
  • 94987 14k

You need this if...

A vacuum test at the port indicated fails to hold at least 18 in-Hg.

  • 94987 14k test