For modern vehicles:
Generally Every 5 years regardless of distance travelled.
That applies for pretty-much every vehicle I've seen in the last 10 years.
Read the manufacturers recommendations and then assess your particular circumstances.
Generally, if I've got a car that i'm unsure of it's maintenance upkeep, I'll go through and replace all such fluids, replace filters and give the car a good mech-check.
Every other oil change.
Once every three months you should change the coolant in your 2003 S10 ZR2. ?æDifferent models and makes of vehicles may require you to change the coolant more or less often.
My ACURA mechanic said @ 125,000 miles to change the Engine Coolant in my 2005 Acura TL.
It is often useful as a coolant because it can absorb thermal energy without a large change in temperature.
B = Change engine oil and filter.5 = Change engine coolant.
First check your coolant level,then change your "ect" engine coolant temp sensor.If that fails change your therostat and coolant.
Recommend every 2 years
Likely a faulty coolant temperature sensor. Change the sensor.
Every time you change the coolant.
Good question. I'm trying to find the answer myself. Closest I find is in the owner's manual on page 199, where it says "Replace engine coolant" without any mileage or time numbers.
With engine coldDrain coolant from radiatorRemove hose clamps on defective hoseRemove defective hose and replaceRe-fill coolant slowly to prevent an air lockStart engine and look for leaksRun engine to normal operating temperature with heater onRe-check coolant level
Engine coolant.