A750F Shift Kit 2003-2007

Lexus LX470, GX470 and Land Cruiser 100 owners usually find this part after a frustrating drive: the truck will not shift past second, the check engine light comes on with P0751, or it pulls away from a stop in a high gear. This listing is a single new S1 shift solenoid for the 2003-2007 A750F four-wheel-drive five-speed, referenced to 35240-60010 and 35240-34010. Our catalog title says shift kit, but this is not a valve body kit. It is one solenoid. For the TransGo valve body repair kit, see the A750F shift kit, 2003-up.

How S1 controls gears in the A750F

The A750F is the 4x4 version of the A750E. The gearbox is the same, with a transfer case added behind it. For 2003 it replaced the older four-speed in the Land Cruiser 100 and LX470 and went into the new GX470 and 4x4 4Runner. Toyota's computer chooses gears by switching two on/off solenoids, S1 and S2, which shift the hydraulic valves that route oil to each clutch and brake. S1 is energized in 1st and 2nd and off in 3rd, 4th and 5th. Parts counters call it 3-way transmission solenoid No. 1, and generic scan tools call it SSA. Sonnax gives its resistance as 11 to 15 ohms.

What a failed S1 feels like

• Stuck on: the truck shifts 1-2 and stops there, falls back to 1st when 4th is commanded, and goes to neutral when 5th is commanded. At highway speed this can feel like a sudden loss of drive.
• Stuck off: it launches in 4th and runs 3rd in place of 2nd, which feels like a heavy, sluggish takeoff, especially in a 5,000-plus pound Land Cruiser or LX
• P0751 stored after two trips with matching gear errors
• P0973 or P0974 for an S1 circuit fault such as a broken coil or a damaged harness pin

Confirming the diagnosis

These trucks are now 18 to 23 years old, so check the simple things first. Toyota's own trouble list for P0751 includes the SLT line pressure solenoid, a blocked valve body and internal clutch or brake damage, not just S1. Check the fluid level and condition with the engine warm. Then use a scan tool with Toyota's Active Test to command gears below 30 mph and see whether the transmission follows. Unplug S1 at the valve body and measure it against the 11 to 15 ohm range. If the solenoid passes but the gear errors persist, a worn or varnished valve body is the likely cause, and an A750E/F valve body for 2003-2007 is the fix. Several solenoid codes at once point toward the full A750F solenoid kit.

Fitment

Titled for 2003-2007 A750F applications: Land Cruiser 100 and Lexus LX470 (2003-2007), Lexus GX470 and 4x4 4Runner (2003 on), 4x4 Sequoia (2004 on), 4x4 Tacoma V6 and Tundra (2005 on), and the 2007 FJ Cruiser 4x4. The 2WD A750E uses the S1 position too. Early and later solenoids can differ in bracket shape, so compare your old part number and bracket with the photo before ordering. If you have any doubt, send us the year and VIN. All parts for these units are on our Aisin transmission parts page.

Install notes

On the Land Cruiser and LX, the pan sits behind the transfer case crossmember and skid plate, so allow extra time. Drain, drop the pan, remove the filter and locate S1 on the valve body. Disconnect it and remove the bracket bolt. Fit the new solenoid with a lubricated O-ring and tighten the bolt to factory torque. These units run hot when towing, so if the fluid is dark, consider an A750E/F overhaul kit rather than a solenoid on a worn unit, and check the cooler circuit. Refill with Toyota WS and set the level at the temperature the factory procedure calls for. Clear the codes and test in both 4WD high and 2WD where your system allows.

Does this fit a 2005 Lexus LX470?

The 2003-2007 LX470 used the A750F, and this solenoid fills its S1 position. Check that the bracket and part number match your old solenoid, or send us the VIN to confirm.

Why is it titled shift kit?

That is a cataloging error on our side. The item is a single S1 shift solenoid, not a valve body kit. The TransGo A750 kit is sold separately.

Can I test S1 without dropping the pan?

Toyota's Active Test lets a capable scan tool command each gear below 30 mph and compare it with the actual gear. A resistance check of the solenoid itself is done at the valve body connector with the pan removed.

What else should I replace while the pan is off?

The filter and pan gasket at a minimum. If there are lockup or pressure codes as well, the other solenoids on the same valve body are worth considering.

Which fluid does the A750F take?

Toyota WS. Fill and check the level by the factory procedure at the specified fluid temperature.