Replacement front planetary carrier for the Toyota/Lexus U660E 6-speed, for units with stripped pinions, chewed splines, or gear noise in the lower gears.
This front planetary carrier assembly is for the Aisin-built U660E six-speed that sits behind the 3.5L V6 in the Toyota Camry, Highlander and Sienna and the Lexus RX 350. Buyers usually find it after a front-drive unit starts whining under acceleration, or after a teardown turns up loose pinions and a chewed spline. The package includes the carrier with pinions, the ring gear, the gear shaft with its bushing, a snap ring and two thrust washers, and it weighs about 6 lb.
Toyota's U660E has two gearsets. ATSG calls the front one the U/D (underdrive) planetary and lists it at 66 sun, 21 pinion and 110 ring teeth; the rear one is a Ravigneaux set. The front set takes engine torque and sends a reduced-speed output to the C1 clutch, which ATSG shows applied in first through fourth. That makes it the hardest-working gearset in the lower gears, and the bushing in the gear shaft and the two thrust washers carry its side load. When they wear, the pinions lose their mesh pattern and noise follows.
A front-drive Camry or ES-style chassis has fewer noise sources than an AWD vehicle, but wheel bearings and the differential side bearings can still mimic gear whine. Drive it on a lift if possible and note which gears are noisy. Pull the pan, check the magnet and cut open the filter. Low or wrong fluid also causes noise and slip, so verify the WS level first using our U660E fluid capacity and service guide, then work through the hydraulic checks in our U660E/U760E problems guide. Metallic debris plus lower-gear noise means a teardown.
Listed for the U660E 6-speed in the Toyota Camry, RAV4, Highlander and Sienna and the Lexus RX 350 with the 3.5L V6. The same family is built as the U660F for AWD models, and the gear train is shared, but internal parts changed by year, so compare your old carrier against this one for spline count, tooth count and pinion layout before assembly. Send us the year and VIN if you want a second check. See every part for this family on the U660E collection page.
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Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Yes. ATSG lists the U660E as one Ravigneaux set plus a U/D planetary; the U/D set is the one many parts catalogs call the front planetary.
The carrier with pinions, the ring gear, the gear shaft with its bushing, a snap ring and two thrust washers.
The U660F shares the U660E gear train, but compare tooth and spline counts before installing. The U760E is a separate family with its own parts listings, so match your old parts rather than assuming.
Not if the noise is from the gearset. Clutches and seals do not correct worn pinion needles or splines; the carrier has to be replaced.
Toyota WS ATF. After filling, set the level at 185-194 F using the overflow check in Toyota's service bulletin.
