The valve that stops water from running through the heater core is not working. I can't find one before I put a quarter turn valve in thought I would ask if anyone knows where to get one.would like it to work like it should

 

NAPA can get them.

 

I believe the one that they will bring in is actually for a gasser truck. And is a 3/4 and 5/8 nipple, instead of a 3/4 x 3/4.

 

Try
Murray Climate Control 74865 - Vacuum Non-Bypass Closes Heater Valve | O'Reilly Auto Parts

 

I picked one up with the correct 5/8" hose fittings.

 

But the ones on our 1st Gen's are 3/4 x 3/4. Not sure why you would have a 5/8 hose, unless someone swapped it?

 

Mine is 5/8's. Always has been from the day I bought the truck in early 98.

 

On my trucks the tubing & the hoses are 5/8. Just double checked with the calipers -- thought maybe my memory was wrong.

 

Mine is 3/4". Wonder if it has something to do with the factory cold weather package mine has.

 

Yes it is. Even the gasser Dodges up there had larger hoses. I was stationed up there for a year in the USAF. I was a vehicle mech.

 

Well I learned something new today. I just always assumed the diesels had the bigger heater hoses, compared to the gassers. Guess I was wrong.

 

The artic packaged Dodges had stuff you would not see down here in the lower 48. The USAF artic pack trucks came with larger heater cores and hose. A battery trickle charger. A battery heater pad. A block heater. The radiator was a little smaller than a lower 48 radiator was. It also had a different antifreeze in it. When it was cold the antifreeze looked like a thin jelly. When warm it flowed like water. The bad part is was corrosive. So you had to keep up on antifreeze service or it would eat out the radiator and heater core.

 

Very interesting...never heard of that package before. Thanks for the enlightenment!