Automatic Transmission

*Oil to Water

1 pass

* Torque Converter Notes

10% is slippage in a normal torque converter. If bolts are too long on a torque converter it'll cause a dimple on the clutch pack. This creates low surface area.

*Govenor

Acts as a hydraulic speedometer senses vehicle speed in order to control upshift or downshift.

Advantage of using a fluid exchange machine ?

Almost replaces all of the ATF even in the torque converter. Neutral in car engages transmission pump

*Valve Body

Brain of trans. allows the transmission to upshift and downshift automatically. Most modern valve bodies are electronically controlled.

*Compound Gear-sets

Contain multiple sun gears, planetary pinion carriers, pinion gears, and internal ring gears in different combinations.

*Most automatic transmission failures are caused by ?

Contamination Water going inside vent may cause contamination. Vent transmission to cause less stress on seals.

Bushings

Control alignment of shafts, drums, and other rotating parts.

Clutch Pack

Designed to transmit power to or hold a member of a planetary gear-set. Uses fluid or springs to apply and release the clutches. .

Drum

Driven by the input shaft contains one or more clutch packs that transfer power to the planetary gear-sets.

*Operation of planetary gear-set

Driving, Driven, Held

*Parallel Shaft Transaxle

Example of a non-planetary transmission. Appearance of a manual transmission

*Restriction in cooler ?

Fluid will not cool effectively

Non-Lock Up Torque Converter

Has the Housing, Impeller, Turbine, and stator. Job is to cause fluid coupling based on engine speed.

Splitter Gear Torque Converter

Has the Housing, Impeller, Turbine, stator, and planetary gear-set. Forms a mechanical linkage between the engine and transmission. Highly effective

Lock Up Torque Converter

Has the Housing, Impeller, Turbine, stator, and pressure plate. Functions Hydraulically and Mechanically. Locks the turbine to the housing.

* Parts of a Torque Converter

Housing, Impeller,Turbine, stator Housing is attached to the flex plate. Impeller is the driving member of the torque converter and rotates engine speed, also drives the pump. Turbine faces impeller and it's hub is attached to the input shaft. Stator Located in between Impeller and Turbine attaches to stationary hub on pump.

Servo

Hydraulically powered piston that operates a rod or pin to apply a band. Neoprene type seals.

*If ATF fluid is brown ? If ATF fluid is Pink ? If ATF fluid is black ?

If ATF fluid is brown it's either contaminated or oxidized. If ATF fluid is milky or pink it's contaminated by water or coolant. If ATF fluid is black and smells burned clutch is prob slipping.

*Accumulator

In clutch apply circuit control shift feel and timing

Torque Converter

Located between the engine and the transmission. Acts as a fluid coupling. Transfers torque from the engine to the transmission.

Types of Automatic Transmissions

Mechanical, Hydraulic, and Electronic

*Oil to Air

Multi Passs

*Necessary to remove transmission in order to replace cooler ?

No

3 Types of Torque Converters

Non-Lock up, Lock up, SplitterGear Torque Converter

*Simple Planetary Gear-set components

One ring gear, One sun gear, one planetary pinion carrier with pinion gears, and one internal ring gear.

*Simpson Gear-set

One sun gear two planetary pinion carriers, and the internal ring gears. (Three forward one reverse gear ratio.)

*Pressure Regulator Valve

Provide the correct amount of hydraulic preassure to the transmission

Flex plate

Provides a connection between the crankshaft and the torque converter. Made of (steel) slightly flexible. Flexible because torque converter gets hot.

Pump

Provides hydraulic flow in a Automatic Trans. Creates a low pressure area on it's suction side. Types of pumps Gear, Rotor, Vane

Input Shaft

Provides power to the gear-set through the clutch pack.

*Planetary Gear-set

Provides under drive, direct drive, overdrive, and reverse by using three basic components in constant mesh.

Types of One-Way Clutch

Roller, Sprag, Mechanical diod, Sprag type allows the trans to coast.

One-Way Clutch

Rotation in only one direction used to hold members of the planetary gear-set.

Torque Converter Phases (3)

Stall Speed Phase, Acceleration Phase, Coupling Stage.

Stall Speed Phase

Stall is when the impeller is rotating but the turbine is stationary. Maximum torque multipulcation

*Lepelletier Gear-sets

Tandem type of gear-set that Include two planetary gear-sets working in a series. do not share sun gears. Planetary pinion, or internal ring gears. (Six forward gears, four reduction, two OD, one reverse.)

Torque converter Split RIngs

The torque converter has split rings, also called guide rings, attached to the impeller and the turbine assembly. These rings attach to the blades of the turbine and the impeller assembly. The split rings direct the fluid in a smooth pattern. They reduce turbulence at the center of the torque converter and improve efficiency.

*Wilson Gear-sets

Three sun gears, three planetary pinion carriers with pinion gears, Three internal ring gears, and one gear assembly pot. (Five forward one reverse.)

Torrington Bearings

Thrush washer with bearing capabilities.

Why are oil pans thin ?

To help dissipate heat

*Why should you change the transmission filter ?

To properly maintain pressure.

*If a clutch pack pack has wrong amount of clearance ?

Too little amount of clearance will cause it to slip. Too much clearance will cause it to drag.

Coupling Stage

Torque converter has the greatest hydraulic efficiency. The turbine is turning at 90% of the speed of the impeller. In this stage, the stator is freewheeling and there is no torque multiplication. As the turbine and the impeller are turning with rotary flow, there is little vortex flow at coupling speed.

Acceleration Stage

Turbine needs to overcome the load required to get the vehicle moving. The vortex flow is the primary flow and the rotary is the secondary flow.

*Ravigneaux Gear-sets

Two sun gears one planetary pinion carrier one internal ring gear. Different size sun gears different sized pinion gears. (Four forward and one reverse.)

*Rules of Planetary Gear-sets

When the external teeth of two gears are in mesh, they rotate in opposite directions. (Sun Gears, Planet Pinion gears) When one gear with external teeth and one gear with internal teeth are in mesh, they rotate in the same direction. (Planet Pinion, Internal ring) If you drive the internal ring gear and sun gear in the same direction, both gears try to rotate the planet pinion gears. (Moves as one unit)

Bands

Wraps around the drum to hold it but cannot rotate (drive) it. One end fixed anchor one end servo. Adjusted by a adjusting screw and locknut. Other bands Selective piston stem.