Transmission Speed Sensor - Input

Remove and replace the input speed sensor on the 2008 Dodge Viper T56 6-speed manual transmission. This sensor is located on the driver's side of the transmission case and requires access from below the vehicle.

Warnings

Tools required

Parts

• Input speed sensor (transmission) × 1 — Mopar 5269705AA or equivalent
• O-ring for speed sensor × 1 — Usually included with sensor

Preparation

1. Park the vehicle on a level surface and engage the parking brake.
2. Place wheel chocks behind the rear wheels.
3. Allow the exhaust system to cool completely if the vehicle was recently operated.
4. Disconnect the negative battery cable to prevent any electrical issues during sensor replacement.
5. Raise the front of the vehicle using a floor jack and support it securely on jack stands under the manufacturer-designated lift points.
6. Verify the vehicle is stable before proceeding underneath.

Procedure

1. 1

   Access the transmission from below
   Position yourself under the driver's side of the vehicle with adequate lighting. Locate the input speed sensor on the transmission case. Verify the exact sensor location and orientation against factory service documentation for the 2008 Viper's rear-mounted TR-6060 transaxle before proceeding. The sensor has an electrical connector and is threaded into the transmission case. Note: Verify correct Mopar part number against factory parts catalog for the 2008 Viper TR-6060
2. 2

   Clean the sensor area
   Use a wire brush to clean any dirt, debris, or road grime from around the sensor body and electrical connector. This prevents contamination from entering the transmission when the sensor is removed. Wipe the area clean with shop towels.
3. 3

   Disconnect the electrical connector
   Locate the electrical connector on the input speed sensor. Press the locking tab on the connector and pull it straight off the sensor. If the connector is difficult to remove due to corrosion or tight fit, use a small flathead screwdriver to carefully release the locking tab while pulling on the connector body (not the wires).
4. 4

   Position the catch pan
   Place a small catch pan or container directly beneath the input speed sensor. Expect a small amount of transmission fluid (typically 2-4 ounces) to drain from the sensor port when the sensor is removed.
5. 5

   Remove the input speed sensor
   Using a 10mm socket and ratchet, carefully loosen and remove the input speed sensor bolt. Verify the sensor retention method against factory documentation. If bolt-retained, remove the retaining bolt with the appropriate socket; if the sensor threads directly into the case, back it out carefully. Once the bolt is removed, carefully pull the sensor straight out of the transmission case. Some transmission fluid will drain from the port as the sensor is withdrawn.
6. 6

   Inspect the sensor port and old sensor
   Examine the sensor port in the transmission case for metal debris, sludge, or damage to the threads. Inspect the old sensor for physical damage to the reluctor pick-up tip or wiring. Check the old O-ring on the sensor body for cracks, deformation, or deterioration. Note that some fluid seepage is normal, but excessive buildup may indicate a failing O-ring.
7. 7

   Clean the sensor port
   Using shop towels, clean the sensor port opening in the transmission case. Do not allow shop towel fibers or debris to enter the transmission. If using electrical contact cleaner, spray it on a shop towel first, then wipe the port area. Do not spray cleaner directly into the transmission.
8. 8

   Prepare the new sensor
   Inspect the new input speed sensor to confirm it matches the old unit. Verify that a new O-ring is installed on the sensor body. If the O-ring was packaged separately, install it onto the groove on the sensor body. Lightly lubricate the O-ring with clean transmission fluid or petroleum jelly to aid installation.
9. 9

   Install the new input speed sensor
   Carefully insert the new input speed sensor into the transmission case port, ensuring the O-ring does not roll or pinch. Push the sensor in until it is fully seated and the bolt hole in the sensor aligns with the threaded hole in the transmission case. Thread the 10mm bolt through the sensor and into the transmission case by hand to ensure proper thread engagement.
10. 10

    Tighten the sensor mounting bolt
    Using a 10mm socket and ratchet, tighten the input speed sensor bolt. Tighten the bolt snugly to compress the O-ring seal, but do not over-torque. The sensor body is typically aluminum and the threads can be damaged by excessive force. Tighten to the factory-specified torque for the input speed sensor fastener on the TR-6060 transmission (verify exact value against factory service documentation).
11. 11

    Reconnect the electrical connector
    Push the electrical connector onto the new input speed sensor until the locking tab clicks into place. Gently tug on the connector to verify it is securely locked. Ensure the wiring is routed away from the exhaust system and any moving components.
12. 12

    Check transmission fluid level
    Due to the minor fluid loss during sensor removal, check the transmission fluid level. On the TR-6060 transmission, the fill plug is located on the case (verify exact side and location against factory service documentation). The fluid level should be even with the bottom of the fill plug hole when the vehicle is level. Top off with the manufacturer-specified transmission fluid for the 2008 Viper TR-6060 if needed. Verify the correct fluid specification against factory service documentation before adding.
13. 13

    Lower the vehicle and reconnect battery
    Remove the jack stands and carefully lower the vehicle to the ground. Reconnect the negative battery cable. This will restore power to the powertrain control module and allow the new sensor to communicate.

Reassembly

1. Reassembly is completed as part of the installation steps above.
2. Ensure the electrical connector is fully seated and locked before operating the vehicle.
3. Verify no tools or materials were left under the vehicle.

Verification

• Start the engine and verify no warning lights related to transmission speed sensor are illuminated on the instrument cluster.
• With the engine running and the clutch pedal depressed, shift through all gears to verify smooth operation and proper speedometer function.
• Take the vehicle on a test drive and monitor the speedometer for proper operation. The speedometer should display accurate speed without fluctuation or dropout.
• After the test drive, re-inspect the sensor installation area from below for any signs of transmission fluid leakage around the sensor O-ring.
• If a scan tool is available, check for any stored diagnostic trouble codes related to the input speed sensor (typically P0715 or P0717).

Related trouble codes on this vehicle

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