A filter change usually involves:
1. Draining some of the fluid: You'll lose some fluid when you remove the pan to access the filter.
2. Adding new fluid: You then add new fluid to replace what was lost. The amount will vary depending on the van's age, condition, and how much drained out.
Important Considerations:
* Consult your owner's manual: This is the best source for the exact capacity of your Astro's transmission and the recommended procedure.
* Partial vs. Full Flush: A filter change is often part of a *partial* transmission fluid change. A *full flush* requires specialized equipment and replaces almost all the fluid. A full flush requires significantly more fluid.
* Overfilling is bad: Adding too much fluid can damage your transmission.
Instead of trying to determine a specific amount beforehand, focus on this:
1. Drain the fluid.
2. Replace the filter.
3. Check the fluid level using the dipstick (with the engine running and at operating temperature). Add fluid *only as needed* to reach the correct level indicated on the dipstick.
Without knowing the year and model of your Chevy Astro, giving a precise fluid amount is impossible and potentially harmful. Always refer to your owner's manual for the correct procedure and specifications.
