U660F Planetary, new and ready to install. Fits the U660F. Ships fast from the USA.
If your all-wheel-drive Highlander, Lexus RX 350, Sienna or Venza has developed a whine that rises and falls with road speed, or the pan came off full of glitter, the gearset on the input side of the U660F is a prime suspect. This is a new underdrive (U/D) planetary kit for the U660F, also built to fit the front-drive U660E. Going by the product photo, the kit is a complete gear package rather than a bare carrier: the U/D carrier with its pinions installed, the ring gear, the gear shaft, a retaining snap ring, a needle thrust bearing and two thrust races.
ATSG's U660E service information lists just two gearsets in this family: a Ravigneaux set and a simple U/D planetary with a 66-tooth sun, 21-tooth pinions and a 110-tooth ring. The U/D set sits between the converter and the clutches and gives the C1 clutch a reduced-speed input, so it is carrying torque in every gear where C1 is applied, first through fourth. The F suffix adds the drive to the rear wheels through the transfer, but the gear train inside the case is the same, which is why one kit serves both versions. On a heavy AWD vehicle that tows or climbs, those pinion needles see a lot of load and heat, and once they wear the pinions start to rock on their shafts.
Gear noise is easy to mistake on an AWD vehicle. A dry rear drive unit, transfer bearing or wheel bearing can sound similar, so listen with the vehicle on a lift and the rear driveshaft removed if you can. Pull the pan and look at what is on the magnet: fine gray paste is normal, flakes and needles are not. Check the fluid level hot first, because a low level causes its own noise and slip; the method is covered in our U660E fluid type and capacity guide, and the common hydraulic faults are in our U660E and U760E problems guide. If the noise only appears in the gears that use C1 and the debris is metallic, plan on a teardown.
This kit is listed for the U660E and U660F transaxles in Toyota and Lexus vehicles, with the Highlander called out. ATSG's application list runs from 2006 to 2011 for the family; units were also used in later years, and internal parts changed over that span. Lay your old carrier and ring gear next to the photos and match the tooth counts and spline count before you build it in. If you are not sure which unit you have, send us the year and VIN and we will check it. You can browse every part for this family on the U660E/U660F collection page.
For a lower-cost set with a different washer package, compare the U660F planetary listed for 2006-up.
| Fits | U660F |
| Part type | Planetary |
| Condition | New |
| Brand | OEM |
| Reference | U660E |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It is listed for both. The U660F is the AWD version, and the gear train inside the case is shared with the U660E. Compare tooth and spline counts with your old parts before installing.
Based on the product photo: the underdrive carrier with pinions, the ring gear, the gear shaft, a snap ring, a needle thrust bearing and two thrust races. Clutches and seals are not included.
No. The underdrive planetary is inside the case, so the transaxle has to come out and be torn down. Most shops do it as part of a full overhaul.
Toyota WS ATF. After a rebuild, fill it and then set the final level with the fluid at 185-194 F using the overflow check procedure in Toyota's service bulletin.
It can be, but rule out the rear drive unit, transfer and wheel bearings first. Metal flakes or needles in the pan along with speed-related whine make the planetary much more likely.
