Transmission fluid is the life blood of your transmission. Proper wear and synchronization depends on using correct fluid. DO NOT USE aftermarket fluid in this transmission. Use only GM Synchromesh (part# 12345349), Pennzoil Synchromesh or Mobil1 ATF. Any other fluid used may cause premature wear and grinding synchronizers and will VOID YOUR WARRANTY.
NOTE: You can use standard Dexron III ATF for break-in, but it must be drained after the break-in period and replaced with Synchromesh or Mobil1 ATF as your permanent fluid.
Filling Transmission Case:
- If you removed the rubber bung from the tailhousing during test fitting, replace before filling transmission or, if available, install your driveshaft.
- Remove the square headed filler bolt located on the side of the main case about half-way up. (lower hole is the drain plug)
- Using a hand operated fluid pump, install 2 quarts of GM Synchromesh (part# 12345349) found at any GM dealership or Pennzoil Synchromesh (same stuff but cheaper) found at big box retailers like AutoZone. After 2 quarts, slowly add fluid until it reaches 1/8” from the bottom of the fill hole when transmission is level. You can easily test this by placing your small finger in the hole to the first knuckle. You should be able to feel the fluid by bending your finger.
- The TKO 500 & 600 Tremec transmissions require approximately 2.42 quarts.
The 6 Speed Tremec Magnum transmissions require approximately 3.45 quarts.
- Replace the filler bolt.
- Store extra Synchromesh in an airtight container in a dry environment to prevent water absorption. Improperly stored fluid should be discarded.