* Water Pump Failure: A failing water pump can't circulate coolant effectively. This leads to overheating, which can cause the engine to shake (due to uneven power delivery from misfiring cylinders caused by overheating) and eventually leak coolant. A failing pump might leak directly, or cause pressure buildup leading to leaks elsewhere.
* Head Gasket Failure: A blown head gasket is a serious issue. It allows coolant to leak into the cylinders or oil, and vice versa. This can cause the engine to overheat, misfire, lose power, and shake. White smoke from the exhaust is a strong indicator.
* Radiator Leak: A crack or leak in the radiator itself, especially at a seam or connection, would explain the coolant loss. However, shaking at 60 mph is less directly related to this unless the overheat from the loss is causing the shaking.
* Coolant Hose Leak/Crack: A cracked or deteriorated hose can cause a significant coolant leak. This is usually more easily spotted than a radiator leak.
* Thermostat Stuck Closed: A stuck closed thermostat prevents coolant from circulating properly, leading to overheating and potential damage, including engine shaking.
* Worn Motor Mounts: While less directly related to the coolant loss, worn motor mounts could exacerbate the shaking issue *especially* at higher speeds like 60 mph. A failing engine mount can allow the engine to move excessively, leading to vibrations that are felt in the cabin.
* Wheel Balance/Alignment: Though less likely, an unrelated issue like poor wheel balance or alignment can contribute to shaking at speed. However, this wouldn't typically be associated with coolant loss.
Interconnection: It's important to note that these problems can be linked. For example, overheating from a water pump failure or head gasket issue can stress other components and lead to further damage, including hose leaks.
Diagnosis: To diagnose the problem accurately, a mechanic needs to inspect the car. They'll likely check:
* Coolant level and condition: Looking for oil contamination (milky appearance).
* Coolant hoses: For cracks or leaks.
* Radiator: For leaks or damage.
* Water pump: For leaks or bearing wear.
* Engine block and head: For external leaks.
* Exhaust: For white smoke (indicating coolant in the cylinders).
* Motor mounts: For looseness or wear.
* Pressure test the cooling system: This can help pinpoint leaks.
Don't drive the car extensively if you suspect a coolant leak, as overheating can cause severe and expensive engine damage. Get it checked out by a mechanic as soon as possible.
