Toyota U660E / U760E 6-Speed Automatic Transaxle Power flow

[thejameskan]

good work here

[xtremetom180]

love the work here

[nesgael1]

@ pustr117 Part 2: gear set to rotate or restricts a gear set from rotation. the gears are always in contact but you get one ratio with the brake on the outer ring gear applied and another ratio with the outer ring gear spinning freely, From this point all the engineers had to do is, determine the combinations and sequence of breaking and releasing needed for all the different forward gears combinations and reverse. This is well explained in the presentation and is the focus in the video.

[MrGizmo757]

i Want to see a Demo on how the new Duble clutch automatics work. its an automatic that uses actuayl geared input and output shapfts just like a manual. and uses a Double wet CLutching system that somhow can engage one gear before the one before it even releases. i have only seen this on paper so i havent been able to wrap My head around it yet. BMW has one in the new M3. the only thing i do know about them is that they are very tough. you can beat the hell out of them and they wont break.

[WeberAuto]

@MrGizmo757 Hi, I would too, but I don't have access to one yet. It is my understanding that there are two input shafts; a solid shaft inside a hollow shaft. Each has its own clutch disk and is connected to opposite sequence gears. When shifting, one clutch drives one input shaft that drives one gear (lest say 1st gear). Next, to shift into 2nd, the other input shaft is connected to 2nd gear, so you just release the first clutch and apply the second; no synchronizers involved. and so on.

[blackericdenice]

@MrGizmo757 IF U find this info please let me know.

[MoneyMarcMes]

That was pretty cool!!!!

[Toad261183]

nn si puo vedere smontato?!nn ho capito....

[lo9men1]

thanx a lot sir...:)

[dclaver2]

There are some cars that has automatic, but, you can also shift gears like a manual with no clutch pedal. Do you know how that works?

[WeberAuto]

@dclaver2 Hi, Some cars have paddle shifters on the steering wheel, others have a shift handle in the center console that has a plus and minus position allowing the driver to attempt to shift the transmission like a manual transmission. These are still automatics, but allow the drivers to request an upshift or downshift. If the conditions are right to allow the shift, the shift will take place. Some shift requests will not occur because of high or low vehicle speed verses requested gear.

[cvl85]

Whoever that thought this up is absolutely genius.. but You who can explain it clearly is much more smarter..

[bobzeda]

NICE...I understand an automatic now! Cool!

[WeberAuto]

@bobzeda Thank you!

[FloydATC]

39 years old and I _finally_ understand how an AT works, thanks to this brilliant video. Thank you :-)

[WeberAuto]

@FloydATC Thank you for the kind comment. I am glad it was helpful.

[superbajaa]

ko

[venkataragavan123]

During reverse gear, which clutch is engaged? Is it the C1 or C2 clutch?

[WeberAuto]

@venkataragavan123 Hi, In reverse neither the C1 nor the C2 are applied. The input shaft has a sun gear splined to it (under the B3 brake area) that always spins with the turbine of the torque converter; this is the input power path. The B3 brake holds the ring gear resulting in the carrier reversing direction. The B2 brake holds the ring gear of the Ravigneaux carrier front planet gears providing gear reduction.

[venkataragavan123]

Hi.. Thank you for the video. Just one clarification.

What is the purpose of holding F1 roller clutch during the 1st gear operation. Does it stop the ring gear from rotating? If yes, would holding the B2 brake serve the same purpose?

[WeberAuto]

@venkataragavan123 Hi, there are two reason for this:

1. The B2 brake and the F1 roller clutch do accomplish the same task of holding the ring gear of the Ravigneaux carrier front planet gears, but only under acceleration. The F1 Roller clutch would overrun when decelerating resulting in a loss of engine braking.

2. The use of the F1 roller clutch allows an instantaneous synchronous shift into second without needing to release the B2 brake. This allows for a better shift feel.

[ThePustr117]

@WeberAuto you seem to know what you're talking about so i wanted to ask a question. I understand in an automatic transmission that the planetary gearset produces all gear ratios by manipulating what components are in motion and what components aren't in motion, but how does the transmission accomplish that? How does it sync the movement of one of the spinning components with itself? If im not being clear I'll gladly restate the question.

[WeberAuto]

@ThePustr117 Hi, there is a computer that looks at vehicle speed verses throttle angle (and other minor inputs) and controls shift solenoids and pressure control solenoids. The solenoids control valve movement in the valve body. The valve movement controls fluid routing and pressure used to apply different clutch packs. The clutch packs control the various parts of planetary gear sets to accomplish each gear ratio. I hope that helps.

[ThePustr117]

@WeberAuto thanks that helps a lot

[nesgael1]

@ThePustr117 I agree with the answer given but you used the word sync, That process is more applicable to manual transmissions where gear ratios are achieved by shuttling wheel gears to mesh with one another, Gears of different sizes create different ratios and a sync mechanism is needed to smoothly marry and disengage the gears. In the transmission above all the gear ratios are achieved by predetermined combinations of clutches and brakes that allow a gear set to rotate

[paulotav2]

how about puting it in movement for demonstration? dahh :///

[mattkorzenieski]

Cool! Just out of curiosity, since I'm not an ME, just a hobbyist, why is the reverse ratio so high? I could guess since it's simply because we don't need high speeds in reverse, but it's even much higher ratio than the 1st gear. Is that common?

[WeberAuto]

@mattkorzenieski Hi, the high reverse gear ratio makes it easier on the engine and emissions to back up. More transmissions seem to be going to this. We also do not need to boost line pressure in reverse which also improves emissions by not loading the engine so much.

[jansun84]

10p for docter evil! nice vid

[rama821]

nesecito hacer una pregunta en espanol

[jackjackattack94]

Why does this transmission have such bad issues for example a shift flare.

[WeberAuto]

@jackjackattack94 There are two things: There may be a service bulletin for a Transmission Control Module (TCM) calibration update for shift flare concerns. The proper fluid level is especially critical on this transaxle. There is no dipstick and it requires a special fluid level checking procedure with the engine running and a special fluid fill tool(pump). If the fluid level is too low, shift flare can occur.

[artcoif]

Cool video. Thank you so much