Hello everyone. Back again. First thanks for all who helped with the replacement back in March. Upon completion the system I was able to pull and maintained a vacuum as required and the required amount of refrigerant had been added to the system. Now, one last problem I have hopefully. Everything worked great until the past month or two. I did notice the system did cycle on/off sorta frequently (maybe every 30-60 secs) but figured it was not hot enough back then. Going into this spring into now as temps have reached into the 90s, I have noticed what has sounded like a sick cow mooing in pain coming from the condenser area where I replaced the orifice tube. This is also around the time i noticed the cycling "issue". I put the gauges back on and run 45-50 on low and 200-250 on high. As I did not replace the high-pressure switch, I replaced it today with no change in behavior. When I replaced the orifice tube back in the beginning, I unknowingly bought a variable type rather than a fixed so I am wondering if this will account for the noise and/or cycling. I can hear it a little while driving, but it is most prevalent when I turn off the truck but will gradually stop. It's definitely loud enough to get someone's attention.

Replaced
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Evaporator
Accumulator
Compressor
Orifice Tube
High Pressure Switch

 

You might wanna check with the factory part # to see if yours is supposed to be fixed or variable.

 

The system will naturally cycle as system pressure changes. Generally, it cuts out when the pressure gets to high. (which is the way it is supposed to work. ) Cycling frequently though, is generally a sign of being low on charge, or, a blockage in the system. The moaning though, yeah, that likely is the orifice tube.....

 

I purchased the orifice tube (UAC) from Amazon. The search results indicated it fit the truck. First time I've heard of one let alone there being two types. The variable one is supposed to have better performance with climates over 105 degrees. Strike this up to learning experience. Thanks again!

 

Update: Took the truck to a shop to take double check the orifice tube. They were unaware of the variable type. Anyway, when they evacuated and pulled the tube out they verified it was in the correct orientation, but noticed metal shavings on the tube. It was apparent to them I did not flush the condenser when I worked on it. They performed this and put everything back together with a new orifice tube. No noise now. Again.... Lesson learned.