Description

Toyota A-340E, A-340H Technical Manual

I’ve been twisting wrenches since before most of you were born, so let me tell you what you’re looking at. This is the Toyota A-340E, A-340H Technical Manual – a factory-authorized ATSG publication that takes you through the entire teardown and assembly of these overdrive units. 96 pages printed by the Automatic Transmission Service Group, not some aftermarket outfit that copies diagrams until they’re blurry. If you’re working on a truck with an A-340E or A-340H, you need this on your bench.

Teardown: Start with the Right Procedure

Page 3 lays out the disassembly sequence. Solenoid wire routing, throttle cable removal, torque converter unbolting – it’s all there with the torque specs in kg-cm, ft-lb, and N·m. The manual calls out non-reusable parts right in the illustration. That oil seal? Replace it. The gasket? Replace it. Don’t skip steps.

Component Breakdown – Which Sections Save You Real Time

The TOC runs from COMPONENTS on page 19 through OIL PUMP (22), PLANETARY (26), OVERDRIVE SUPPORT (35), DIRECT CLUTCH C2 (39), FORWARD CLUTCH C1 (44), FRONT PLANETARY (50), SECOND BRAKE B2 (54), FIRST & REVERSE B3 (62), VALVE BODY (66), and ASSEMBLY (78). Each section breaks down the snap rings, thrust bearings, races, and clutch clearances. I’ve seen techs waste half a day because they didn’t have the correct end-play spec for the planetary. This manual gives you the numbers.

Second Brake (B2) – A Common Failure Point

Page 54 shows the Second Brake assembly. The piston sleeve, snap ring, and band adjustment are critical. If you get the brake band clearance wrong, the transmission will slip under load. The manual includes the specified torque for the adjusting pin lock nut: 260 kg-cm (19 ft-lb, 25 N·m). Don’t guess. Use a torque wrench.

Is This Manual for the Home Garage Mechanic?

Yes, if you’re comfortable reading exploded diagrams and following a numbered sequence. This isn’t a Chilton’s with vague drawings. The ATSG manual expects you to have basic hand tools, a press, and a dial indicator. But the instructions are written for someone who has time to do the job right. For the professional shop, it’s a must-have. I keep a copy at bay 3 for any A-340E or A-340H that rolls in.

Source Authenticity: ATSG vs Aftermarket Reprints

The Automatic Transmission Service Group worked directly with Toyota Motor Company to produce this. They thank Toyota for the illustrations and information. That means the clearances, the spring counts, the check ball locations – all verified. Aftermarket manuals often skip the torque values or use generic ones. Not this one. Every fastener on the valve body has a spec. You can compare it with the Automotive Industry Overview from Toyota’s own site to cross-check.

If you’re rebuilding transmissions regularly, look at the Toyota LS400 Technical Manual – Factory 1998 Engine Control System for related electronic diagnostics, or the Toyota Camry SE Technical Manual – 174 Pages of OEM Specs for a different platform. For modern CAN bus systems, the Toyota Camry Technical Manual (2006-2011) – Factory CAN Bus Diagnostics covers that territory.

FAQ

Does this manual cover the A-340H hydraulic version?

Yes. Both E and H variants are covered from page 3 onward.

What torque values are listed for the valve body bolts?

On page 66, the valve body section lists specific torque specs for each bolt. The manual includes both kg-cm and ft-lb values, but you’ll need a calibrated torque wrench — don’t trust a beam-type for these low ranges. Also note that the manual specifies the non-reusable parts like gaskets and seals. If you skip replacing those, you’ll get leaks. I’ve seen it happen, and the labor to redo a valve body job is not cheap. The manual also warns about solenoid wire routing — get that wrong and you’ll fry the computer on the E model. So follow the exact sequence on page 68.

Don’t waste time hunting through forum posts for torque specs that may or may not be right. You’ve got the real data here. Access the Factory Manual and get back to your workbench.