99 OBS Tahoe Coolant Issue

[jeffwest5599]

I have a 1999 tahoe with the old body style. I notice that my coolant overflow reservoir never has any coolant in it. I also check the radiator from time to time and it is a little low. I have looked everywhere and cannot seem to find where it is leaking. Any ideas on what this coudl be and what I can do to keep this form happening. Any help is appreciated. Thanks.

Jeff

 

[bsamoul]

Is your intake manifold gasket leaking? That's where all my coolant was going.

 

[99Yukon_Z71]

If there are no visible leaks around the radiator, water pump, hoses, etc, then most likely your lower intake manifold gaskets are leaking, but beforehand, check the heater fitting on the right hand side, its a common problem for leaks, cracked radiator housing and whatnot.