Posts Tagged ‘Transmission’

Manual transmission test drive

Now, (with caution – safety first!), shift the transmission lever into neutral. Apply the parking brake. With the engine idling, press the clutch pedal all the way, hold it down, and listen for noises. Then release the pedal and listen for noises again. There should be no loud noises at either positions. The next step [...]

LTSEO Posted in Transmission TestLTSEO

Automatic transmission test drive

Use more caution when test-driving someone else’s vehicle – the mirrors, the driver’s seat, etc. may not be adjusted properly for you. First, get use to brake pedal feeling, adjust the mirrors, driver’s seat, and learn all the controls of the vehicle. Proceed to drive only when you sure it’s safe. One of the indications [...]

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Transmission repairs

There are several problems that can be resolved with an adjustment (A simple adjustment is one that can be made without removing the transmission from the vehicle.) or minor repair. If a late model transmission (computer-controlled transmissions started becoming popular in the early ’90s) is not shifting properly, it is often the result of a computer [...]

Automatic Transmission Maintenance

Transmission fluid should be changed periodically.  Your owner’s manual should give you the recommended intervals which could be anywhere from 15,000 miles to 100,000 miles.  Most transmission experts recommend changing the fluid and filter  every 25,000 miles. Few transmissions have drain plugs to drain the old fluid.  In order to get the fluid out, the [...]

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Seals and Gaskets

An automatic transmission has many seals and gaskets to control the flow of hydraulic fluid and to keep it from leaking out.  There are two main external seals: the front seal and the rear seal. The front seal seals the point where the torque converter mounts to the transmission case. This seal allows fluid to [...]

Computer Controls , Governor, Vacuum Modulator, Throttle Cable

Computer Controls The computer uses sensors on the engine and  transmission to detect such things as throttle position, vehicle speed, engine speed, engine load, brake pedal position, etc. to control exact shift points as well as how soft or firm the shift should be.  Once the computer receives this information, it then sends signals to [...]

Valve Body

The valve body is the control center of the automatic transmission.  It contains a maze of channels and passages that direct hydraulic fluid to the numerous valves which then activate the appropriate clutch pack or band servo to smoothly shift to the appropriate gear for each driving situation.  Each of the many valves in the [...]