How do I replace the surge tank on 2002 GMC Yukon. Need to check for a leak in tank. Could leak be in hose from surge tank to water puml? Can not see any water leaking except for water on right side in front of tire. Could surge tank cap be bad and force water out over flow hose?

Chances are that the hoses to and from the tank are brittle and the moving around formed a crack in a hose. Double check the connections to the tank.

Coolant leaks can be difficult to trace because the leak can migrate away from the source. To start with, dry off all areas that are wet. Then ,with a flash light, inspect the hose and water pump to see where the leak originates. This is done with the engine running so be mindful of all moving parts as you look through the engine compartment. It may be the hose that is leaking.

it is over heating,thermostat stuck close,water pump weak.

Remove the tank & check it out

Either it has a hole or the hose going to it
leaks

Your vehicle is equipped with a surge tank. There is no opening in the radiator itself. To check or add coolant (antifreeze) to your cooling system, screw the cap off of the surge tank.

CAUTION: Do this only when the engine is cool.

This is covered on page 5-26 of the 2004 GMC Yukon Owners Manual.

To download a free PDF version of the 2004 GMC Yukon Owners Manual click here

Hello: Check the coolant level if the surge tank is not at proper level (threre is a full line on the container) If the container is low then you may have a leak in your cooling system.

Escalade, Suburban, Tahoe, Yukon, Denali, DenaliXL, YukonXL 1999-2005 Water Pump - Removal & Installation 4.8L, 5.3L & 6.0L Engines

1. Remove or disconnect the following:
   Air outlet duct Coolant Inlet radiator hose from the water pump Upper fan shroud Cooling fan and clutch assembly Drive belt Radiator outlet hose from the coolant pump Surge tank hose Heater hose Water pump
   
   
   Fig. Exploded view of the water pump assembly-4.8L, 5.3L and 6.0L engines
   

To install:

NOTE DO NOT use cooling system seal tabs (or similar compounds) unless otherwise instructed. The use of cooling system seal tabs (or similar compounds) may restrict coolant flow through the passages of the cooling system or the engine components. Restricted coolant flow may cause engine overheating and/or damage to the cooling system or the engine components/assembly.

1. Install or connect the following:
   Water pump. Install the water pump bolts. Tighten the water pump bolts first pass to 11 ft. lbs. (15 Nm); tighten the bolts final pass to 22 ft. lbs. (30 Nm). Water pump drive belt pulley and bolts (if applicable). Tighten the pulley bolts first pass to 89 inch lbs. (10 Nm); tighten the bolts final pass to 18 ft. lbs. (25 Nm). Surge tank hose Heater hose Outlet radiator hose to the coolant pump Drive belt Cooling fan and clutch assembly Upper fan shroud Inlet radiator hose to the water pump Air inlet duct Coolant

1. Remove or disconnect the following:
   Air inlet and outlet duct Coolant Inlet radiator hose from the water pump Upper fan shroud Cooling fan and clutch assembly Drive belt Radiator outlet hose from the coolant pump Surge tank hose Heater hose Water pump
   
   

To install:

1. Install or connect the following:
   Water pump. Install the water pump bolts. Tighten the bolts to 11 ft. lbs. (15 Nm) for the first pass; then tighten to 22 ft. lbs. (30 Nm) for the final pass. Water pump drive belt pulley and bolts (if applicable). Tighten the bolts to 89 inch lbs. (10 Nm) for the first pass; then tighten to 18 ft. lbs. (25 Nm) for the final pass. Surge tank hose Heater hose Outlet radiator hose to the coolant pump Drive belt Cooling fan and clutch assembly Upper fan shroud Inlet radiator hose to the water pump Air inlet and outlet duct Coolant

Hope this help to solve it (remember comment and rated this).

Water Pump Replacement (4.8L, 5.3L and 6.0L Engines)
Removal Procedure
1. Drain the cooling system.
2. Loosen the air cleaner outlet duct clamps at these locations:

Throttle body

Mass Airflow/Intake Air Temperature (MAF/IAT) sensor
3. Remove the radiator inlet hose clip from the outlet duct.
4. Remove the air cleaner outlet duct.
5. If necessary, remove the engine sight shield.
6. Remove the radiator vent inlet hose from the radiator hose clips.
7. Reposition the inlet hose clamp at the water pump.
8. Remove the inlet hose from the water pump.
9. Remove the fan blade.
11. Reposition the outlet hose clamp at the water pump.
12. Remove the outlet hose from the water pump.
13. Reposition the surge tank outlet hose clamp at the water pump.
14. Remove the surge tank outlet hose from the water pump.
15. Reposition the heater inlet hose clamp at the water pump.
16. Remove the heater inlet hose from the water pump.
17. Remove the water pump bolts.
18. Remove the water pump and gaskets.
19. Discard the water pump gaskets
Installation Procedure Important: All gaskets surfaces are to be free of oil or other foreign material
during assembly.
1. Install the water pump and NEW gaskets
2. Install the water pump bolts.
3. Install the heater inlet hose to the water pump.
Zoom Sized for Print
Notice: Refer to Fastener Notice in Service and Precautions.
2.1. Tighten the bolts a first pass to 15 Nm (11 ft. lbs.).
2.2. Tighten the bolts a final pass to 30 Nm (22 ft. lbs.).
4. Position the heater inlet hose clamp at the water pump.
5. Install the surge tank outlet hose to the water pump.
6. Position the surge tank outlet hose clamp at the water pump.
7. Install the outlet hose to the water pump.
8. Position the outlet hose clamp at the water pump.
9. Install the accessory drive belt.
10. Install the fan blade.
11. Install the inlet hose to the water pump.
12. Position the inlet hose clamp at the water pump.
13. Install the engine vent inlet hose to the radiator hose clips.
14. If necessary, install the engine sight shield.
Important: Align the arrow at the throttle body end of the duct with the throttle
body attaching stud.
15. Install the air cleaner outlet duct
16. Install the radiator inlet hose clip to the outlet duct.
17. Tighten the air cleaner outlet duct clamps at these locations:

Throttle body

MAF/IAT sensor Tighten the clamps to 7 Nm (62 inch lbs.).
18. Fill the cooling system.

I hope this helps. The numbering is incorrect in the sequence but the instructions are correct.

Roy

I assume the vehicle has a heater in the rear. If so, the problem is probably either the heater core leaking, a hose leaking, or a hose connection leaking. If you want to further investigate and possibly fix yourself, let me know.

I also have a sunroof that leaks on a 2002 Yukon. It is a factory sunroof with a cracked seal. Where can I get a new seal?