U660E Shift Kit

First-generation V6 Camrys, the 2008 Avalon and the early Lexus ES 350 are old enough now that their six-speed automatics have well over a hundred thousand miles of valve wear on them. The usual complaints are a 2-3 shift that bangs back and forth or runs up in rpm, slipping when you accelerate in 3rd or 4th, and torque converter lockup codes. If the clutches are still healthy, this TransGo SK U660E kit is the low-cost repair: three sets of drop-in valve parts that put the worn hydraulic circuits back in spec without replacing the whole valve body.

What the kit fixes in the U660E valve body

Toyota's U660E controls every shift with solenoids, but the solenoids can only be as accurate as the oil that feeds them. TransGo traced the common failures to three places. The B2 regulator outer valve wears its bore, oil escapes, and the 2-3 shift shuttles. The solenoid modulator valve, which limits how much pressure reaches the solenoids, wears until solenoid feed and line pressure drift. The TCC boost valve and bushing wear until lockup no longer applies and releases on command. In the box you get a hardened B2 outer valve with a white spring, a new solenoid regulator valve with bushing, orange spring and sleeve, and a hardened TCC boost valve and bushing, plus a 0.055 in. drill bit. No reaming fixture is needed; the parts are designed to work in the existing bores.

Symptoms on early U660E cars

• Shuttling or flaring on the 2-3 upshift, often worse when warm
• Slip with throttle applied in 3rd and/or 4th
• Lockup slip codes and rpm that rises and falls at steady cruise
• Erratic shift feel that does not match any stored electrical code

Rule out the easy causes first

Gears Magazine reports that aging U660E cars commonly develop a harsh coast downshift, and that a dirty throttle body or a slow mass airflow sensor can produce downshift complaints that look like a transmission fault. Clean or test those first. Check fluid level and condition at operating temperature with Toyota's WS bulletin procedure, since a low sealed unit flares on its own. Scan all modules and read freeze frame data. If the fluid is black and the pan has friction debris, a shift kit is no longer enough. Our U660E and U760E service guide goes deeper on each step.

Fitment

The source listing names the 2007-2009 Toyota Camry 3.5L, 2008 Avalon 3.5L and 2007-2008 Lexus ES 350 3.5L. That is the same SK U660E part TransGo rates for U660E and U660F units from 2006 to 2018, so later V6 models are covered by the kit as well; see the U660E shift kit 2007-up listing for the longer vehicle list. It does not fit the four-cylinder U760E. Confirm the transaxle code on the ID plate, or give us year and VIN. Browse everything for this unit on the U660E parts page.

Install notes

• Work on a clean bench and keep each valve train in order as it comes out; small parts such as plastic and steel check balls have set locations.
• The new B2 outer valve and solenoid regulator parts reuse the original end plug or retainer where the instructions say so. No retainer may sit above the casting surface.
• Enlarge the two separator plate holes with the provided drill; TransGo ties this to keeping the unit cool.
• If testing shows a solenoid fault as well, a U660E solenoid kit can go in during the same service. Slipping clutches call for a U660E master rebuild kit.
• Refill with Toyota WS ATF and set the level at 185-194 F. The U660E fluid guide has the fluid details.

Does this fit a 2010 or later Camry V6?

The kit itself is TransGo's SK U660E, rated for 2006-2018 U660E units, so a later 3.5L Camry is covered. This listing's source names the 2007-2009 Camry, 2008 Avalon and 2007-2008 ES 350 specifically.

Shift kit or replacement valve body: which do I need?

If the castings and solenoids are good and the complaint matches the 2-3 flare, 3rd/4th slip or lockup slip pattern, the shift kit repairs your existing valve body for less. If bores are badly damaged or solenoids are failing, a replacement valve body is the faster route.

Will it make my car shift harder?

Its purpose is to restore correct pressure control, not to add a firm aftermarket shift. TransGo describes it as correcting flare, slip and lockup complaints.

What is included?

A hardened TCC boost valve and bushing, a hardened B2 regulator outer valve and spring, a new solenoid regulator valve with bushing, spring and sleeve or end plug, and a 0.055 in. drill bit, with TransGo instructions.

What fluid does the U660E use?

Toyota WS (World Standard) ATF. Check the level hot, at 185-194 F, using Toyota's bulletin procedure.

• Toyota Aisin U660E/U760E Problems and Service Guide
• U660E Fluid Type and Capacity