My 93 4x4 with the 5.0 is slowly losing coolant. None of it is dripping or leaking, nor do I smell any coming from engine compartment or exhaust.

Some passengers tell me they can detect an "exhaust" smell in the cab while my AC or heater is on.

I'm loosing maybe a quart every 1000 miles.

What I'm not hoping for is a bad head gasket.

Just looking for some ideas of how to diagnose. Thanks.

Chuck

 

check your radiator cap for a good seal it might be escaping from that do you hear any hissing or strange noises?

 

get the truck nice and warm then check your oil, if it is not a milky color its not a head gasket (unless it is the head gasket and it is leaking out the side of the block.) or into the cylinder but then you would have white smoke rolling out the tail pipe

look under your heater box.

 

Thanks for the help; I have not noticed the oil with any milkshake color, all good and oily. I have not noticed any external leaks anywhere . . . so I'm going to hope a new rad cap will fix it.

Chuck

 

check where ur rad meets ur water pump

 

Id say heater core. My s10 lost coolant in a similar fashion and I could smell it in the cab, but no visible external leak. Turned out to be the heater core, how good does it blow heat?