U660F Clutch Drum 2007-2009

If your early six-speed Toyota or Lexus V6 slips on takeoff, flares between gears or has stopped moving forward while Reverse still pulls, the forward/direct clutch drum is one of the first hard parts to suspect. This is the early-production drum for 2007-2009 U660F and U660E transaxles, rebuilt and sent out loaded. According to the listing it comes with four new forward clutches and four new forward steels, three new direct clutches and three new direct steels, a new forward piston and retainer, a new direct piston, and the 8-lug direct piston retainer and housing, all assembled on an input shaft that measures about 9 1/4 inches.

What the forward/direct drum does in a U660F

The U660F is the all-wheel-drive version of the U660E; both share this drum. It sits at the front of the gear train on the input shaft, which the torque converter turbine drives. Inside are two driving clutches. ATSG's U660E technical information lists C1, the forward clutch, as applied in first through fourth, and C2, the direct clutch, as applied in fourth through sixth, with both on together in fourth. Apply oil reaches the two pistons through sealing rings on the shaft, so worn ring lands or a cracked piston leaks pressure and lets a pack slip. Because the drum is in the power path in every forward gear, it takes the full torque of the 3.5L V6 that these transaxles sit behind.

Symptoms that point to this drum

• Engine flares or a soft, late bite pulling away from a stop
• Slip in fifth and sixth, or a long, flaring 4-5 upshift
• No forward gears at all while Reverse still works
• Burnt WS fluid and clutch lining on the pan magnets
• Gear ratio or slip codes after a long highway run or a grade

How to confirm it before ordering

Start with the whole vehicle. Gears Magazine advises scanning all modules and using Toyota's Check Mode, and notes that a dirty throttle body or slow MAF sensor can cause harsh coasting downshifts with no transmission fault at all. Next, check the WS fluid hot at the overflow plug, because a low level imitates a slipping clutch. Then put a gauge on the case: ATSG's U660E pressure tap chart shows separate C1 and C2 taps alongside line pressure. Good pressure plus slip means the problem is inside the drum. Low pressure on every tap sends you to the pump and valve body instead, and our U660E and U760E problems guide covers the valve bores that wear and drop pressure.

Fitment: early 2007-2009 units

This listing is for the early drum, covering 2007-2009 U660F and U660E transaxles. Per Gears Magazine, the U660E launched in the 2007 Camry and ES350, reached the Avalon for 2008 and the Venza for 2009, always behind a V6. Toyota changed the drum later in production, and early and late versions are not swapped casually. Before you buy, confirm the transmission tag reads U660E or U660F and not U760E, count the lugs on your direct piston retainer and compare them with this 8-lug design, and measure the shaft. A 2010-and-later unit should use the late U660F drum. If anything does not match, send us your year, model and VIN before ordering. Everything for this family is on the U660E and U660F parts page.

Install notes

• Flush the cooler and lines first; old lining material will otherwise feed straight into the new packs and the solenoids.
• Inspect the case bearing support bore. Gears Magazine reports this family wears the case where the main gear train bearing mounts, and any movement in the outer race means the case must be repaired before a new drum goes in.
• Install new shaft sealing rings, lubricate them with WS fluid, and air-check C1 and C2 through the case passages before the valve body goes on.
• Verify clutch pack clearance to the factory figure.
• Fill with Toyota WS fluid, set the level using the hot procedure in our U660E fluid capacity guide, then run the ECT memory reset with a scan tool that can actually perform it.

A drum is only one pack. The other clutches, bands and gaskets come in the U660F master rebuild kit, and a rebuilt U660F valve body is worth pricing if the old drum failed from low pressure.

How do I tell the early 2007-2009 drum from the late one?

Check your year first, then compare your old drum with the photos. This early drum uses an 8-lug direct piston retainer and a shaft about 9 1/4 inches long. If yours differs, send us your VIN before ordering.

Does it fit both the U660E and the U660F?

Yes. The listing gives both the front-drive U660E and the all-wheel-drive U660F. It does not fit the four-cylinder U760E, which uses its own drum.

Is it ready to install or do I add clutches?

It arrives loaded with new forward and direct clutches, new steels and new pistons. Gaskets, seals and the other clutch packs still come from a rebuild kit.

Can a failed forward clutch cause no Drive but Reverse works?

Yes. The forward clutch in this drum is applied in first through fourth, so a burnt C1 pack or leaking piston can leave Drive dead while Reverse still pulls.

What fluid and relearn does it need?

Toyota WS fluid, with the level set hot at the overflow plug in Toyota's temperature window. Clear the adaptive values afterward with the ECT memory reset on a capable scan tool.

• Toyota/Aisin U660E and U760E: Shudder, Valve Body Wear, and the WS Fluid-Level Procedure
• U660E Fluid Type, Capacity and Service Interval