If I didn't get 275,000+ with normal driving, I would be mad. The 3.4 is one of the finest motors they ever built.
120 000 miles
With proper maintenance and without abuse probably 200,000 miles
The cam chain will last the life of the engine and need not be replaced until the engine is overhauled.
At least 200,000 miles.
200,000 miles is average with normal maintenance.
The average life expectancy of an engine in a Ford Focus is around 150,000 - 250,000 miles. You can extend the life expectancy of your engine by making sure you do regular maintenance and upkeep on it.
Honda, Toyota, and Nissan about the life of the vehicle. GM about 60,000 miles (crappy).
I have a 1999 with 200,000 miles on it and still running strong.
Your 2004 Toyota 4Runner has a timing belt if it is a V8. This belt must be replaced every 90,000 miles. Warning: This is an interference engine. Severe engine damage will be done if the belt breaks. If you have a V6 then it has a chain which should last the life of the engine.
If Taken Care Of These Engines Will Give You Over 200,000 Miles.
forever
average life of a 3.1 v6 with proper oil changes and tuneups lasts about 160,000 miles according to common reviews on engine life