Consumer Reports has a feature that provides estimates for repair work by vehicle type and location. This is the estimate range for a '97 4Runner w/ 3.4L in Chicago area.......
Head Gasket Replacement
To prevent an expensive, recurring problem, the integrity of the entire cooling system should be inspected and tested when a head gasket is replaced.,During this repair, the cylinder head(s) will need to be inspected and machined. Additional repairs may be needed after the inspection, which can add several hundred dollars to the repair and are not included in the RepairPal estimate.,Cylinder head gasket replacement often occurs when the engine has high mileage; several additional parts may be needed during the repair. These may include cooling system components (hoses, water pump, radiator, thermostat, etc.) vacuum lines,timing belt, ignition wires, and more. These will be in addition to the RepairPal estimate above.
Common Symptoms
Head gasket failures are often due to an overheated engine, but can also be caused by high mileage and/or age.,An early sign of a failing head gasket will be a rough running engine when you first start the vehicle, especially if it's been sitting overnight. The rough running will generally last for only a few seconds.,A leaking headgasket will often leak engine coolant into the oil, causing a "chocolate milk" like appearance and the oil level my be higher than normal.,Failed head gaskets can produce a white, sweet-smelling smoke from the tail pipe.
Total cost:
$1331 - $2059
Labor: $901 - $1150
Parts: $430 - $909
Engine Oil
Oil Drain Plug Gasket
Oil Filter
Coolant
Head Gasket Set
Gasket Sealer
Good Luck