Checking Coolant
The coolant surge tank is located in the engine compartment on the passenger side of the vehicle. See Engine Compartment Overview on page 10‑6 for more information on location.
The vehicle must be on a level surface when checking the coolant level.
Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down. If coolant is visible but the coolant level is not at or above the FULL COLD mark, add a 50/50 mixture of clean, drinkable water and DEX-COOL coolant at the coolant surge tank, but be sure the cooling system is cool before this is done.

The coolant level should be at or above the FULL COLD mark. If it is not, there may be a leak in the cooling system.
See also:
Uniform Tire Quality Grading
Quality grades can be found where applicable on the tire sidewall between tread shoulder and maximum section width. For example:
Treadwear 200 Traction AA Temperature A
The following information rel ...
Potential Issues
Some OnStar services are disabled after five days. OnStar cannot perform Remote Door Unlock or Stolen Vehicle Assistance after the vehicle has been off continuously for five days. After five days, OnS ...
How to Check Lubricant
To get an accurate reading, the vehicle should be on a level surface.
1500 Series
A. Fill Plug
B. Drain Plug
All Except 1500 Series
A. Fill Plug
B. Drain Plug
• When the differential is c ...





