AW4 Automatic Transmission Fluid and Filter Service
Drop pan, replace filter, refill with Dexron III/Mercon (or modern multi-vehicle ATF equivalent). Pan drop nets ~4 qt; full system holds ~8 qt.
The AW4 is an Aisin-Warner four-speed automatic spec'd by the FSM for Dexron II/III ATF, not ATF+4. A 2006 service bulletin reaffirmed Dexron over Chrysler's later ATF+4 standard. Modern Dexron VI or a multi-vehicle ATF (Maxlife, Mobil Multi-Vehicle) is the popular consensus pick today since true Dexron III is no longer licensed. Capacity for a pan drop and filter is about 4 quarts; a full fluid exchange/torque-converter flush is 7.5-8 quarts. The AW4 has no dipstick tube full-system drain - either drop the pan repeatedly with refills between, or pull a cooler line and pump fresh fluid through while the engine idles. The filter is held by four bolts to the valve body and uses a rubber-tipped pickup that must seat against the new pan gasket. Always use a new Mopar or Beck/Arnley pan gasket - reusable cork gaskets weep. Check level hot, in Park, on level ground; the dipstick has HOT and COLD ranges.
Why it works
- Cheap longevity insurance for a bulletproof box
- Restores firm 2-3 shift
Trade-offs
- Pan-drop captures only half the fluid
- Filter bolts strip easily
Tools required
- 10mm socket
- drain pan
- torque wrench
- gasket scraper
- funnel with long neck
Parts
| Part | Vendor | Est. price |
|---|---|---|
| AW4 filter kit | RockAuto | ~$25 |
| Pan gasket | Mopar | ~$12 |
| Dexron VI ATF (8 qt) | any | ~$50 |
Sources
Related
Written and maintained by an AZ wheeler and driveway wrencher. How we source guides. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.