Transmission Flush

This procedure performs a complete transmission fluid exchange on the 2008 Dodge Viper 6-speed manual transmission, draining old fluid and refilling with fresh Pennzoil Synchromesh 75W-90 to maintain smooth shifting and transmission longevity.

Warnings

Tools required

Parts

• Transmission drain plug washer/gasket × 1 — Use OEM specification
• Transmission fill plug washer/gasket × 1 — Use OEM specification

Fluids

• Pennzoil Synchromesh 75W-90 — 4.2 qt

Preparation

1. Park vehicle on a level surface and engage parking brake.
2. Place wheel chocks behind rear wheels.
3. Allow transmission to warm to operating temperature by driving 5-10 minutes, then let cool for 10-15 minutes until warm but safe to touch.
4. Raise front of vehicle with floor jack at designated front jacking point and support on jack stands under frame rails.
5. Raise rear of vehicle and support on jack stands at rear jacking points, ensuring vehicle is level front-to-rear.
6. Verify vehicle stability before working underneath.

Procedure

1. 1

   Locate transmission drain and fill plugs
   Position yourself under the vehicle with a flashlight. Locate the transmission case on the passenger side of the driveline tunnel. Identify the drain plug on the bottom of the transmission case (10mm hex) and the fill plug on the driver's side of the transmission case approximately mid-height. Clean the area around both plugs with a wire brush to remove debris.
2. 2

   Remove fill plug first
   Using a 3/8" drive ratchet with 10mm hex bit, loosen and remove the fill plug from the driver's side of the transmission case. This ensures you can refill the transmission after draining. If the fill plug cannot be removed, do not proceed with draining. Inspect the plug washer/gasket for damage and have a replacement ready if needed.
3. 3

   Position drain pan and remove drain plug
   Place the drain pan directly under the transmission drain plug, positioned to catch fluid that may flow toward the rear initially. Using the 3/8" drive ratchet with 10mm hex bit, slowly loosen the drain plug. Remove the drain plug by hand for the last few turns and pull away quickly to avoid fluid contact. Allow transmission fluid to drain completely, which will take approximately 10-15 minutes.
4. 4

   Inspect and clean drain plug
   Once fluid flow has stopped completely, inspect the drain plug threads for damage or metal debris. Remove the old washer/gasket from the drain plug and discard. Clean the drain plug threads and sealing surface with a shop rag. Wipe the transmission case drain hole seating surface clean of any old gasket material or debris.
5. 5

   Reinstall drain plug
   Install the new washer/gasket onto the drain plug. Thread the drain plug into the transmission case by hand to avoid cross-threading. Tighten the drain plug to manufacturer specification using a torque wrench. Verify the exact torque specification for the Tremec T-56 drain plug against the factory service manual before final tightening; do not overtorque the aluminum transmission case.
6. 6

   Prepare fill equipment
   If using a fluid transfer pump, fill the pump reservoir with fresh manufacturer-specified manual transmission fluid (verify exact spec for the 2008 Viper Tremec T-56 — commonly a Chrysler-specified MTF; confirm against factory service manual). If using a funnel and hose, attach a hose extension long enough to reach from the fill hole to a convenient location where you can pour fluid. Position the pump nozzle or hose end into the fill hole.
7. 7

   Fill transmission to proper level
   Slowly pump or pour the manufacturer-specified manual transmission fluid into the transmission through the fill hole. The transmission is filled to capacity when fluid begins to flow out of the fill hole. Fill until a steady drip or small stream exits the fill hole, indicating proper level. Verify total fluid capacity against the factory service manual before filling. Allow excess fluid to drain out for 30-60 seconds to establish the correct level.
8. 8

   Install fill plug
   Wipe the fill plug threads and install a new washer/gasket if the plug uses one. Thread the fill plug into the transmission case by hand, then tighten to manufacturer specification using a torque wrench. Verify the exact torque specification for the Tremec T-56 fill plug against the factory service manual before final tightening; do not damage the aluminum case threads.
9. 9

   Clean and inspect for leaks
   Wipe both the drain and fill plug areas clean with shop rags. Inspect both plugs for any signs of fluid seepage. Check the area around the transmission case for any other leaks that may have become apparent during the service.
10. 10

    Lower vehicle
    Remove jack stands from rear of vehicle and carefully lower rear to ground using floor jack. Remove jack stands from front of vehicle and lower front to ground. Remove wheel chocks.

Reassembly

1. No disassembly was required beyond plug removal; reassembly consists of plug installation as detailed in the procedure.

Verification

• Start the engine and allow it to idle for 30 seconds, then shut off.
• Check under the vehicle for any transmission fluid leaks at the drain and fill plug locations.
• Test drive the vehicle through all gears, verifying smooth shifting with no grinding or difficulty engaging gears.
• After test drive, recheck the area under the vehicle for leaks with the vehicle on level ground.
• If any leaks are present, verify plugs are properly torqued and washers/gaskets are correctly installed.

Related trouble codes on this vehicle

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