The automatic transmission in a 2000 Toyota Tundra typically uses Dexron II/III automatic transmission fluid, while the manual transmission uses a GL-4 gear oil in the 75W-90 range. Always verify with the owner’s manual or the transmission dipstick for your specific vehicle configuration.
Automatic transmission fluid (ATF)
The 2000 Tundra’s automatic transmissions (the A340/A340F family) are designed to run on Dexron II/III-compatible ATF. Dexron II, Dexron II-D, Dexron III, or Dexron III-H are commonly cited as acceptable options by service guides. Using the correct spec helps ensure smooth shifting and protects transmission components from wear.
Compatible ATF options commonly used in this transmission family include:
- Dexron II ATF (including Dexron II-D)
- Dexron III/III-H ATF
Conclusion: For the automatic transmission, use Dexron II/III-compatible ATF as specified for these models. Avoid fluids not listed as compatible with Dexron II/III unless explicitly approved by Toyota for your exact transmission. Dexron VI is generally not recommended for older automatics unless a Toyota service bulletin or manual allows it.
How to verify the correct ATF
Check the owner's manual, the transmission dipstick label, or consult a Toyota dealer to confirm the exact fluid specification for your VIN, as there can be variations by transmission code or production date.
Manual transmission fluid
The manual transmission in many 2000 Tundra models typically requires a GL-4 gear oil in the 75W-90 viscosity range. This specification helps protect synchronizers and gears in a manual gearbox and differs from automatic transmission requirements.
Common manual transmission fluid option:
- 75W-90 GL-4 gear oil
Conclusion: Use 75W-90 GL-4 gear oil for the manual transmission. Avoid GL-5 oils or fluids not specified for a GL-4 manual transmission, and verify with the manual or dealer for your exact build.
Summary
- Automatic transmission: Dexron II/III-compatible ATF (e.g., Dexron II, II-D, III, III-H)
- Manual transmission: 75W-90 GL-4 gear oil
For the most reliable guidance, always reference the specific owner's manual for your truck’s VIN and transmission code, or contact a Toyota service professional.