truck has not been sitting up and yes I have to keep adding AF once a week and I have not seen no leaks only smoked when starting up after driving it go away . thanks for all replys

 

Take vacuum line off of tranny and see if fluid runs out

 

I am quite certain a F150 could not be ordered with a C6 in 1994. The transmission has to be a 4R70W or an E4OD. Both are 100% computer controlled with no vacuum connection to the engine.

I do know of a few F350s with C6s up to 1996/1997. Seriously doubt the OP has a C6 in this truck unless someone did a swap.

 

If you have to keep adding coolant regularly and there's no sign of where it is going - then yes, bad headgasket, cracked head, cracked block, etc., are your options - unfortunately.

 

ty for the for reply
I had a feeling that was it.
ty

 

i had few people tell me to put some seal in radiator that seal head gasket.
I don't have funds to have replace so has anyone ever tried this before? thanks

 

IMO youd be better off to tear it down and replace the gasket. With the sealers most of the time you have to flush all the coolant and run straight water then you add the sealer to the motor and you have to drive about 500 miles before you can drain it out and replace the coolant. Not something you'd really want to try in the middle of winter.

 

had truck in shop today. they did few test. they said head gasket seem be ok. they said they did find intake manifold leak. I have wait till they get time do it.