Most automatics use the planetary gears to provide various reductions ratios. Bands and
clutches are used to hold various portions of the gear sets to the transmission case or to
the shaft on which they are mounted. Shifting is accomplished, then, by changing the
portion of each planetary gear set which is held to the transmission case or to the shaft.
Servos/Accumulators
The servos are hydraulic pistons and cylinders. They resemble the hydraulic actuators
used on many other machines, such as bulldozers. Hydraulic fluid enters the cylinder,
under pressure, and forces the piston to move to engage the band or clutches.
Servo operation
The accumulators are used to cushion the engagement of the servos. The transmission
fluid must pass through the accumulator on the way to the servo. The accumulator housing
contains a thin piston, which is sprung away from the discharge passage of the
accumulator. When fluid passes through the accumulator on the way to the servo, it must
move the piston against spring pressure, and this action smoothes out the action of the
servo.
Hydraulic Control System
The hydraulic pressure used to operate the servos comes from the main transmission oil
pump. This fluid is channeled to the various servos through the shift valves. There is
generally a manual shift valve, which is operated by the transmission selector lever, and a
shift valve for each up shift the transmission provides.
Summary of Contents for TrailBlazer
Page 1: ......
Page 26: ...Fig 3 Typical body and undervehicle maintenance locations Refer to chart for descriptions ...
Page 29: ......
Page 30: ......
Page 31: ......
Page 175: ...Spring free length check Valve spring squareness check ...
Page 192: ...Front of piston mark ...
Page 361: ...5 3L Engine Except Saab Underhood Fuse Block 2003 2005 Early Production ...
Page 469: ...Removing the outer band from the CV boot Removing the inner band from the CV boot ...
Page 470: ...Removing the CV boot from the joint housing Clean the CV joint housing prior to removing boot ...
Page 471: ...Removing the CV joint housing assembly Removing the CV joint ...
Page 472: ...Inspecting the CV joint housing Removing the CV joint outer snap ring ...
Page 473: ...Checking the CV joint snap ring for wear CV joint snap ring typical ...
Page 474: ...Removing the CV joint assembly Removing the CV joint inner snap ring ...
Page 475: ...Installing the CV joint assembly typical ...
Page 553: ...9 Torque the lug nuts to specification 10 Lower the vehicle ...
Page 556: ...Toe in Frame Misalignment Frame misalignment ...
Page 588: ...Bleeding caliper ...
Page 624: ...Manifold gauge set components Refrigerant recovery recycling station ...
Page 676: ...A C Specifications ...
Page 677: ......