* Overfilling: This is the simplest explanation. Someone may have added too much fluid during a service. Check the transmission fluid level using the dipstick (if applicable, some transmissions require special procedures) *when the engine is running and the transmission is at operating temperature*. Overfilling can cause pressure buildup and lead to fluid leaking out of seals or vents.
* Internal Transmission Failure: A failing transmission pump, worn seals, or a cracked case can cause internal pressure to build and force fluid out. This is a serious problem requiring professional diagnosis and likely a significant repair. Look for signs beyond just overflowing, such as slipping gears, harsh shifting, unusual noises, or low fluid level after the overflow.
* Cooling System Issues: While less common, a cracked or damaged transmission cooler (often integrated into the radiator) can allow coolant to mix with transmission fluid, causing an increase in fluid volume and overflow. This will often result in milky-looking fluid.
* Incorrect Fluid: Using the wrong type of transmission fluid can cause problems, potentially leading to increased pressure and overflow. Always use the type specified in your owner's manual.
* External Leaks: Although you're seeing an overflow, there might be a leak elsewhere that's forcing the system to compensate by pushing out excess fluid. Carefully inspect the transmission and surrounding areas for any signs of fluid leaks.
How to Troubleshoot:
1. Check the fluid level correctly: Ensure the van is level, the engine is running, and the transmission is at operating temperature (drive it for a while). Use the dipstick (if equipped) to check the level and compare it to the manufacturer's specifications in your owner's manual.
2. Inspect for leaks: Look for wet spots, drips, or fluid stains under the vehicle, paying close attention to the transmission, cooler lines, and pan.
3. Check the transmission fluid's condition: Is it the correct color and consistency? Milky fluid indicates a coolant leak into the transmission. Burnt-smelling fluid suggests internal problems.
4. Seek professional help: If you've checked the fluid level and found no external leaks, it's best to take the Windstar to a qualified transmission specialist or mechanic for diagnosis. Transmission problems can be complex and costly to repair, so getting a professional opinion is crucial.
Ignoring a transmission fluid overflow can lead to serious and expensive damage to your transmission. Don't delay seeking professional help if you can't identify the cause.
