Toyota U660E / U760E 6-Speed Automatic Transaxle Power flow

Weber State University (WSU) - Automotive Technology Department - Transmission Lab. Toyota U660E / U760E 6-Speed Automatic Transaxle Power flow. The U660E / U760E transaxle is a 6-speed Aisin transaxle used in Toyota Camry and Lexus ES350. This transaxle uses a ravigneaux planetary gear set (with long and short pinion gears in the same planet carrier)

This video helps demonstrate NATEF Task A2.C.10. " Diagnose transmission/transaxle gear reduction/multiplication concerns using driving, driven, and held member (power flow) principles.", a priority 2 task.

Download the U660E Power Flow Table here: http://www.weber.edu/wsuimages/automotive/T-TEN/Toyota%20U660E%20Power%20Flow%20Table.pdf

http://www.weber.edu/automotive

This video was created and edited by John D. Kelly at WSU. For a full biography, see http://www.weber.edu/automotive/J_Kelly.html

Visit my other youtube channel https://www.youtube.com/user/vibratesoftware to see the amazing NVH app for vibration diagnosis!

This is a demonstration
of the power flow

through the planetary
gearsets of a Toyota U660E

automatic transaxle.

This transaxle was
founded in 2007

and later Toyota
Camrys and Lexus ES

350s with the V6 engine.

This transaxle is unique in
that it uses the RAVENOL gearset

with the long and
short pinions, which

I describe in a separate video.

We have power from
the torque converter

from the engine connected
to our input shaft.

This input shaft
goes all the way

to the back of the
trans, clear back here,

and connects to this
housing right here.

So as I turn this housing,
the input shaft also turns.

Inside of this housing, the
direct multiple clutch housing

is the C1 clutch
and the C2 clutch.

These are clutches that
are going to be rotating

and turning parts of
the planetary gearset.

We have the F1
roller clutch that

only rotates in one direction.

We have to B2 brake, the
B3 brake and the B1 brake.

These are clutch packs
that when they come on,

they stop these
components from rotating,

but only one or two
at a time depending

on which gear we're in.

The output to the final drive,
there's a big drive here

that we had to press off
of this to get it apart,

but it meshes with the final
drive idler and final drive

ring gear to propel the
vehicle down the road.

So our power comes
in from the engine,

any time this spline
shaft right here turns,

the vehicle is
going to be moving.

And so what I want to do is
walk you through the different--

six different gears forward and
reverse to see how all of those

are accomplished using the
different clutches and roller

clutches.

So for first gear, we are
going to apply the C1 clutch--

that's this clutch right here--

and in this demonstration,
what I've done

is I've got some
sheet metal screws

that I can run in and grab
the housing that the C1

clutch would normally grab.

The C2 clutch, I've
got it released.

So I've connected the
C1 clutch housing,

which is underneath
this housing,

to this housing that's
connected to the input.

So we're going to turn the
C1 clutch, and in first gear,

we're going to have the F1
roller clutch, this one right

here.

It's held solid by the case--
these big lugs are just

splined right to the case.

So, let's see--
the engine is going

to be turning clockwise in
relation to my demonstration.

So I'll hold the F1 clutch
and I will turn the C1 clutch.

And what that should give us
is a gear ratio of 3.3 to 1.

So we'll have to turn this
housing 3.3 turns to get

one full turn of this output.

So let's give it a shot.

So here we go.

We've got one, two, and three.

So three turns of the engine
gives us one turn of the output

to drive the--

drive the wheels.

Now I'm going to back that
up back to where we were.

So there's one, two, three.

Actually, it was 3.3.

Now, to shift to
second gear, we're

going to keep the
C1 clutch applied,

but now, we're going
to apply the B1 brake.

This is the B1 brake
housing right here.

So we're going to grab that
and stop it from spinning,

and we'll still turn
to see one clutch.

Now this will give us a
gear ratio of 1.9 to 1,

so we should turn this C1
clutch 1.9 turns to get

one turn of the output shaft.

Here we go.

So there's one,
and not quite two--

1.9 turns from the engine to
get one turn of the output

to drive the wheels.

Let me back those up.

So that was second gear.

Now we're ready to
go to third gear.

In third gear, we still
keep the C1 clutch applied,

but now we apply the B3 brake.

The B3 brake's right here.

So we're going to let
go of the B1 brake,

we're going to apply the B3
brake and keep it from turning,

and that gives us a
gear ratio in third gear

of 1.4 turns to 1.

So let me get things lined up.

I'll hold that from turning.

I should turn this
one-- a little less

than 1 and 1/2 turns to
get one turn of the output.

So here we go.

There's one turn, and
a little less than 1

and 1/2 turns and we've got
1.4 to 1 gear reduction.

So that was third gear.

Fourth gear is direct drive
on this transaxle, where

we have one turn of
the input gives us

one turn of the output.

And to get that, we're going
to apply both the C1, which is

already on, and the C2 clutch.

So run the little sheet metal
screw in to turn the C2 clutch.

So we're just going to
turn these two pieces.

One of them turns the
sun gear, one of them

turns the ring gear.

And I'm going to let
go of all the brakes,

no brakes are applied, and now
we just have one turn in equals

on turn out--

that's a direct drive,
a 1 to 1 gear ratio.

Now, to shift to
fifth gear, we're

going to let go
of the C1 clutch.

So I'll back this little screw
out for my demonstration,

so that we're just
applying the C2 clutch now.

And we're also going
to apply the B3

brake, which is this one.

So I'll stop the B3
brake from spinning,

we'll turn the C2 clutch, and
in fifth gear, it's a 0.713 to 1

gear ratio.

So we'll turn this
housing about 0.7 turns--

7/10 of a turn--

to get one turn of the
output-- this is overdrive,

so here we go.

We've got one full turn of the
output and about 7/10 of a turn

at the input.

OK, so that was fifth gear.

To go to sixth gear, we're going
to keep the C2 clutch applied,

and now we're going to apply the
B1 brake, which is this brake

right here, and that should
give us 0.6 terms of the input

to one turn of the output.

So here we go.

0.6-- see, that's
really spinning fast.

You have about 6/10
of a turn of the input

to one full turn of the output.

That's our sixth gear,
which is a double overdrive.

So let's go back
to where we began.

Pretty much got all
the labels lined up.

Now let's go to reverse.

To get reverse, we have to apply
the B2 brake and the B3 brake

at the same time.

So we're going to stop both
of those from rotating,

and then we'll turn the
input shaft from the engine.

And since we're going to
be turning it clockwise,

we're going to expect
the output shaft

to turn counter-clockwise.

So I'll try to stop both
of those from turning,

I'll turn the engine.

Notice that we're
spinning backwards.

And in this reverse, it actually
has a really low gear ratio--

it's a 4.18 to 1, so it will
take four turns of the engine

to get one turn of
the output in reverse.

This has been a demonstration
of the U660E power flow

through its gearsets.