A couple of questions, thanks anyone that can help. I know nothing about A/C systems, so some of the questions may be rather dumb.

1. How do you identify the high-side and low-side of the system? Is the low-side the larger fitting at the front of the truck?

2. Does the larger fitting (at the front of the truck) have some type of valve that is different than a standard schraeder (shredder?) valve core? Mine is leaking, even when I just take off the plastic cap, however I can't see a valve core, there is some sort of rubber diaphragm where it looks like the it should be. Along that line, is it possible that some rubber seal has ballooned out over the valve stem and is no longer sealing properly (and possibly the cause of the leak)?

Thanks in advance for any help/advice.

I know I'll have to evac. the system if I replace the valve core or the whole fitting, I'm just not sure if it is a special fitting.

 

The one that is easy to get to (which I think is the one your talking about as the one that is leaking) is the low side. It's up front along the passenger side engine compartment.

Sorry, can't help you with the other part of the question, but, you could always use a metal cap and some teflon tape (instead of the plastic one), to get you by and help slow down the leaking till you figure it all out. KD