U660E Transmission parts, repair guidelines, problems, manuals


Transmission general data

Number of gears Transmission Type Drive ATF (full capacity) L ATF (change) L ATF type
6 AT FWD/AWD 6,5 2,8 Toyota Type WS

The 6-speed automatic transmission U660E designed by Aisin in 2006 for FWD cars Lexus ES350, as well as for the luxury 6-cylinder models (Camry, RAV4, Avensis) for 3.5 lit. The unit was paired with the V6 engine.The U660F unit is intended for AWD crossovers and sedans. The U660 unit is a competitor of ZF 6HP26. In 2009, the U660 unit was complemented by U760E model cured from "common problems" and intened for a bit lower torque from the engine (up to 2.7 l). After some period of time the U761E sub-modification was released for less powerful engines with 2.0-liter capacity. Repair parts for this gearbox are the same as for U760. Among the market competitors of the U760 unit, specialists point out the ZF 6HP21 unit.

What are you looking for?

Overhaul Kit | Friction Kit | Friction | Steel Plate | Steel Kit | Band | Solenoid Kit | Solenoid EPC | Solenoid TCC | Pump | Shaft | Drum | Valve body | Torque converter | Hub | Piston | Piston Kit | Planetary Gear | Filter | Gasket | Bushing | Seal | Bearing | Pressure Plate | Stator | Differential | Retainer | Inhibitor Switch | Instruction manual | TOOLS & ACCESORIES | Sensor

Related transmission models or modifications of this transmission:

Which cars run with this gearbox?

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Technical issues and repair guidelines

Friction lining of the lockup unit is not the most crucial problem for driving, but it is critical for the “health” of this transmission. The torque converter is the main "contaminator" and the source of all problems of clogged valve body and solenoids. This gearbox usually covers 200 thousand kilometers, but the driver can significantly cut its service life by an aggressive driving style. Almost all major repairs of this gearbox include the torque converter repair. The torque converter repair with replacement of worn-out friction lining every 150-250 thousand kilometers (depending on the driving style) allows saving of some money on the valve body replacement.

According to judgement of experts, the most common problem of the U660E unit is related to the main housing bearing, which is attached to a “weak” circlip. The drum of Direct package is one more problem of this gearbox. Many gearboxes with short mileages (only70-100 thousand kilometers) were handed in for the overhaul and replacement of burnt clutch cover С1-С2 - Drum (Direct) in the assembled condition. Another issue is related to wear-out and burning of frictions in braking packages B1-B3 (gears 2 and 6). The most frequently replaced component is a set of frictions in the package C1/C2 (gears 1-4). Generally the whole set of friction components is replaced.

Valve body and solenoids in U660E

The most common problem for all 6-speed automatic gearboxes is the worn valve body. The problem with the valve body, which operated with damaged torque converter lockup and contaminated ATF, is related to wear-out or slagging of channels and plunger-valves of the valve body. The most frequently replaced component in the electrical part is the selector position plate with temperature sensors. The overheated temperature sensor is often considered to be the reason of the valve body malfunction. The first reason of early issues with electrical components (before covering 200 thousand kilometers) is the automatic transmission overheating. Almost each overhaul of overheated U660E transmission is accompanied with the order of pistons kit. The list of spare parts that may be damaged in this sophisticated gearbox as a result of neglected bearing vibrations is quite large (crown gear, sun gear, planetary gears, differential, pistons).

It should be taken into account, that all abovementioned problems with the U660 unit are common for very old or quite worn-out automatics. A high percentage of cars equipped with U660 serve before covering standard 200 thousand kilometers (in many cases even longer) without any repairs under the condition of timely ATF change and filter replacement.