A340E Planetary, used and ready to install. Fits the A340E. Ships fast from the USA.
If the A340E four-speed in your Toyota 4Runner, Tacoma, T100, Tundra, Supra or Lexus SC is whining in first and reverse, slips or has no drive in one range, or came apart with a scorched rear gearset and glitter in the pan, this is the part you are shopping for. It is a used A340E rear planetary assembly that came out of a 1999 4Runner. It was inspected before listing: no pitting or heat discoloration, the sealing ring surface is smooth, the bushing is good, and the planet pinions turn smoothly with no roughness.
The A340E stacks an overdrive planetary in front of a three-speed Simpson gear train, which uses a front and a rear planetary that share one sun gear. The rear planetary is the set that does the heavy lifting at the bottom of the range. Toyota's own description of the unit lists two components whose whole job is to hold the rear planetary carrier: the 1st and reverse brake (B3) locks it in both directions, and the No. 2 one-way clutch (F2) stops it turning backward. With its carrier held, the rear set is the reaction point for the 2.804 first gear and the 2.393 reverse ratio, so it sees the highest torque in the transmission every time the truck pulls away or backs up a trailer.
Gear noise and slipping have different causes, so test before you buy hard parts. Start with fluid level and condition, then run a stall test and a time lag test. In the Toyota factory procedure, a long N-to-R lag or a high reverse stall speed points at the direct clutch or the 1st and reverse brake, and our guide to checking transmission line pressure shows how to rule pressure in or out. If pressure and lag times are in spec but you have a speed-related whine in first and reverse only, the rear gearset is the prime suspect. Slipping under throttle is covered step by step in Aisin transmission slipping under load. Once the unit is apart, check each pinion for end play, rough rotation and chipped teeth, and look at the carrier lugs and the thrust washers.
This rear planetary was removed from a 1999 Toyota 4Runner A340E. The A340 family went into the 4Runner from 1989 through 2002 plus the Tacoma, T100, Tundra, Supra, Cressida and Lexus SC over a long production run, and the A340F four-wheel-drive version shares the same 2.804, 1.531, 1.000 and 0.705 gear ratios. Even so, Toyota changed internal parts across years, and the heavy-duty case used behind the twin-turbo Supra is not the same transmission. Lay your old rear planetary next to this one and compare the pinion count, the spline count and the lug pattern before you install it, or send us your year and VIN and we will confirm it. Browse more parts for this family on our Aisin and Toyota transmission parts page.
| Fits | A340E |
| Part type | Planetary |
| Condition | Used |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It was pulled from a 1999 4Runner A340E and is the rear gearset of the Simpson gear train used across the A340 family. Internal parts changed over the years, so compare the pinion count, spline count and lug pattern to your old part, or send your year and VIN before ordering.
Usually a whine or growl in first gear and reverse that changes with road speed and fades once the truck shifts into third. The rear set is held by the 1st and reverse brake and the No. 2 one-way clutch, so it is loaded mainly in those ranges.
It is a used assembly. It was inspected with no pitting or heat marks, a smooth sealing ring surface, a good bushing and smooth-turning planet pinions.
Thrust washers and bearings for the rear set, the 1st and reverse brake frictions and steels, and all seals and gaskets. An overhaul kit covers the soft parts. Flush the cooler and lines if the old gearset shed metal.
Use the fluid listed in your owner's manual. Later A340E applications use Toyota Type T-IV ATF, while the 1993 Toyota pickup service manual lists Dexron II. Check the level hot in Park and do not overfill.
