I have a 97 scab 4x4 that I'm having trouble finding a refrigerant leak on. I found a leak on the o-rings where the lines bolt to the compressor and I fixed that but It still has a leak somewhere that for the life of me I can't find, I even do hvac for a living! Is there any common places on these trucks that are known for leaking? I've already checked the seal where the compressor halves are bolted together cause I know that is common and I've checked the Schraders. If anyone could point me in a more specific spot/s to check I would appreciate it

 

Usually when you can't find a leak it's the evaporator core.
Stick a freon sniffer into the drain on it after it's been sitting a while

 

Have you checked the condenser core?

 

Not a bad idea. All I did was pressurize it with nitrogen and stick my head up below the glove box to see if I hear anything. Where about is the drain under the truck?

 

I've checked where the lines connect to the condenser but I have not been able to physically see anything on the face of the condenser.

 

If you soap everything else down under pressure and don't find the leak...... And do a good job at the soaping...... It's likely the evaporator core.

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Rather than have refrigerant escape continually, use some compressed air in the system.
Just don't turn the A/C on when filled with air.

 

I use dry nitrogen. That's how we look for leaks at work

 

Is it possible for refrigerant to leak past the clutch shaft seal? Only place my refrigerant detector goes off is when I stick it between the clutch and the compressor body. but when I spray it with soapy water i don't see any bubbles

 

Yes it's possible to have a leaking compressor shaft seal. I had one on a Toyota after about 20 years.