Autostick

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The name Autostick has been used both for a Volkswagen semi-auto transmission[citation needed] and a system designed by Chrysler which allows for manual selection of gears with an automatic transmission. Another similar system designed by Porsche is called Tiptronic. These systems are also called "Manu-Matic" transmissions.

Volkswagen Autostick[edit]

Marketed as the Volkswagen Automatic Stickshift, the three speed manual transmission was connected to a vacuum-operated automatic clutch. The top of the gear shift was designed to easily depress and activate an electric switch, i.e. when engaged by the drivers hand. When pressed, the switch operated a 12 volt solenoid in turn operating the vacuum clutch, thus disengaging the clutch and allowing shifting between gears. With the driver's hand removed from the gearshift, the clutch would re-engage automatically. The transmission was also equipped with a torque converter, allowing the car to idle in gear, like an automatic. The torque converter was operated by transmission fluid. This would allow the car to stop in any gear and start from a standing stop in any gear.

The Autostick debuted on the 1968 Volkswagen Beetle and Karmann Ghia at mid-model year along with a fully independent rear suspension that debuted in August 1968 for the 1969 model year. VW ended Autostick production with the 1976 model year.

Chrysler Autostick[edit]

The Dodge Intrepid ES and Eagle Vision TSi were the first automobile models in North America that came equipped with the Autostick system as an option, later standard equipment on the 1997 Plymouth Prowler and 1999 Chrysler 300M. It was added to the JA cars on the 1997 Stratus. This system was standard on 1999 to 2003 model year Dodge Grand Caravan ES, but only the front-wheel drive models since the AWD used a different TCM. Many Chrysler models today come with this system, including the 300, 300C, Charger, Challenger, Sebring, PT Cruiser, Crossfire, Pacifica, Chrysler Town & Country, Dodge Avenger, Dodge Stratus R/T, Dodge Journey R/T and SXT and Dodge Grand Caravan.

System advantages[edit]

  • Ability to manually select gears
  • Ability to start from 2nd or 3rd in inclement weather to improve traction
  • Allows downshifting while coming down steep inclines to maintain speed
  • Improved performance with quicker, more firm shifts
  • Removes clutching with pedal, instead it is operated by hand

System components and operation[edit]

Components of the Autostick system in the first Chrysler vehicles to have the design included a different TCM (Transmission Control Module), shift assembly utilizing a unique PRNDL design invented by Peter Gruich in 1994, and gauge cluster. The gauge cluster includes a read-out to let the driver know which gear is selected.

The system works by dropping the shifter down into a gated area on the shift assembly which allows the shifter to be pushed to the right (up-shift) or to the left (down-shift). When the driver pushes the shifter in either of these directions the assembly sends a signal to the TCM to shift up, or down depending on the driver's actions. Dropping the shifter into the Autostick gate while the vehicle is moving will simply keep the vehicle in the current gear selected.

For the column-shift third- and fourth-generation Dodge Grand Caravan ES, Chrysler Town and Country 1999-2003, four speed automatic transmission models with FWD (41TE) or AWD (41AE) transmission only. The Autostick feature is activated by moving the "PRNDL" transmission selection on the steering column clockwise past D where L is usually found. When selected the current gear ratio is not changed, the "Autostick" indicator illuminates in the instrument cluster, the numbers 3 2 1 illuminate to the right of D, and a square appears around the gear currently engaged, D 3 2 or 1. The button on the end of the handle is used to engage/disengage overdrive lockout, the same function as selecting L when not equipped with Autostick. When engaged the transmission will not enter 4th gear and downshifts to 3rd if it is in 4th gear. Specific gears are selected by an up/off/down 3 position momentary switch in the middle of the handle on the PRNDL lever, up to upshift and down to downshift. OD lockout and specific gear selection are mutually exclusive. While in OD lockout the transmission behaves as a 3 speed automatic transmission. Autostick gear selection hold a specific gear 1, 2, or 3 until another gear is selected by the up/down switch, the vehicle comes to a complete stop and Autostick forces a shift to 1st gear, Autostick operation is cancelled by selecting 4th gear, aka D, or Autostick is disengaged by moving the PRNDL.

The service manual explains that Autostick signalling is multiplexed on a single wire. The transmission control module outputs a 5v signal to the handle and monitors it for voltage drop The voltage ranges 0.3-1.6,1.6-2.8, 2.8-3.8, and 3.8-4.8 representing down,up, overdrive lockout, and all open respectively. The vehicle drops into 1st after stopping but can be launched in 1st, 2nd, or 3rd gear. The speed (or cruise) control operates only in 3rd and 4th gear while in Autostick mode and is deactivated if shifted to 2nd gear, just as it would if the driver had braked. Shifting into 4th (aka D) cancels Autostick single gear selection mode, and gears are automatically selected as usual until down or OD lockout is pressed.

System failsafes[edit]

In modern implementations if the user does not shift while driving in the Autostick mode, the transmission will automatically up-shift at redline (the exception being the Plymouth/Chrysler Prowler which will not shift automatically at redline when in AutoStick mode) to prevent engine/transmission damage, and will not downshift into redline. When coming to a complete stop, the system will automatically return to first gear.

References[edit]