Replaces all seven shift, lock-up and pressure control solenoids in the Toyota A750E and A750F five-speed valve body in one job.
If your 2003-2007 Lexus LX470 or 2003-2009 GX470 4.7L V8 has started to bang the 2-3 shift, flare between gears, shudder when the converter should lock, or drop into a single gear with a solenoid code stored, the electrical side of the A750F valve body is the first place to look. This kit replaces all seven valve body solenoids at once in the Aisin A750F five-speed, which Toyota and Lexus documents also call the TB-50LS. The units are remanufactured: the bodies may show cosmetic wear, while the internals and O-rings are new.
The A750F is a five-speed rear-drive automatic built for four-wheel-drive trucks, with the transfer case bolted behind it. Every shift is decided by the transmission computer and carried out by the solenoids on the valve body. On-off shift solenoids move the shift valves to pick the gear. Linear solenoids ramp clutch apply pressure so each shift feels smooth, one sets line pressure, and one controls how firmly the torque converter clutch locks. On a heavy V8 SUV that tows and runs long highway miles, the linear solenoids see constant duty and plenty of heat. As their windings and spools age, the pressure they deliver drifts away from what the computer expects, and the computer cannot correct the shift fast enough.
That last point matters on the A750F. A solenoid can read inside its resistance spec on a cold bench and still misbehave at operating temperature, which is why a full set is the repair that tends to last.
Pull codes and freeze-frame data first. Toyota names each solenoid differently in the repair manual, the parts catalog and the scan tool, so translate the code before you condemn a part (see the sources below for the naming chart). Check fluid level and condition, then inspect the case connector and the internal harness for heat damage or oil wicking. Our guide on bench testing transmission solenoids covers resistance and flow checks, and Aisin harsh or delayed shifts walks through separating an electrical fault from a hydraulic one. If the fluid is black and full of friction material, or the truck slips under load, worn clutches are the bigger problem and a rebuild such as the A750F master rebuild kit is the honest fix.
The manufacturer lists this kit for the 2003-2009 Lexus GX470 4.7L, 2003-2007 Lexus LX470 4.7L, 2008-2011 Suzuki Grand Vitara 2.7L and 2007-2009 Kia Sorento 2.5L and 3.3L, with part references A750, A750E, A750F, TB-50LS and TB50 LS. The Lexus V8 applications are the core fitment. For any vehicle, confirm the transmission tag, the solenoid connector shapes and the number of solenoids on your valve body against the kit before you drain fluid, or send us the year and VIN and we will check it. Browse every unit in our Aisin transmission parts collection.
This is a pan-off job with the transmission in the vehicle. Drain the fluid, remove the pan and filter, unplug the internal harness from each solenoid, and release the retaining clips or bolts. Lightly wet each new O-ring with fresh ATF and press the solenoid straight into its bore so the O-ring does not roll. The retainer bolts thread into the aluminum valve body, so torque them lightly. Reconnect every connector and confirm the harness is clear of the pan.
If a new solenoid set does not cure a lock-up shudder, the separate A750F TCC solenoid or worn valve body bores are the next suspects.
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Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Yes. The manufacturer lists the 2003-2007 LX470 4.7L, which uses the A750F five-speed. Match the solenoid count and connectors on your valve body before installing, or send us your VIN to double-check.
The other solenoids have the same miles and heat history, and the linear pressure solenoids drift with age even when they still pass a cold resistance test. Replacing the set means you only drop the pan once.
Toyota WS automatic transmission fluid. Set the level at the overflow plug with the fluid at the temperature Toyota specifies, using a scan tool to read fluid temperature.
Yes. Clear the codes and reset the transmission adaptive values with a scan tool, then drive the truck through every gear so the computer can relearn clutch fill times.
A new filter and pan gasket at minimum. Inspect the internal harness and replace it if the insulation is cracked or the connectors are loose.
Remanufactured. The bodies may show cosmetic wear, while the internals and O-rings are new.
