i know it sounds stupid, but when i first start my truck when i give it gas it sounds like water sloshing in the glove box,,, there is never water and nothing is wet, no leaks, nothing,,, it usually stops after a minute or so ???

 

Heater core. Air. Bleed your cooling system.

 

^ +1, need to burp the cooling system.

 

Check your antifreeze in the radiator.
Probably a bit low.
The heater core is behind the glove box
and you are hearing the water/air sloshing around.
You might need to "burp " the system to get all the air out.

 

air in the heater core which is.....drum roll..... right behind the glove box.

it will usually work itself out.
if not, check your hoses and water pump for a slight leak thats letting in air when cold. you can burp the air by parking passenger front corner up a steep hill, and with cold engine and radiator cap off, let it warm up and the air will bubble out.

another burp option is to cut the heater hose near the firewall and install a flush Tee with screw on flush cap which will act as an air escape valve.

edit. dang. i type for 3 minutes and get scooped.

 

awesome , thanks guys... sorry for being in the wrong forum.... you all are always so helpful.. i thought i was hearing things at first...