Help With 2003 Yukon Xl A/c

[d-trainSA]

Dear all:

 

I have frequented these forums for advice over the past couple of years however this is my official post.

 

I have two questions if you don't mind:

 

1) I have a 2003 Yukon XL 1500 with a 5.3l flex fuel V8 with dual a/c and automatic climate control. Recently, upon startup of the vehicle, occaisonally, I've been hearing a spraying sound coming from under the hood. I'm fairly confident that this is coming from the A/C compressor as it doesn't happen until the compressor clutch engages and I can smell freon in the air. I'm 95% sure that my seals on the and/or entire compressor is failing and will need to be replaced. My question on this problem is can my compressor be rebuilt with new seals (o-rings) or is it preffered to buy a new compressor? Regardless, I don't have the money to take of this now, so this brings me to my second question.

 

2) My second question has to do with pressures for the A/C system. My service manual tells me to expect 250/50 psi for 95 degree ambient air temp but it doesn't say if this is with only the front A/C on or both front and back on. With only the front on, my pressure are within range however when I turn the rear on as well, I get significantly higher pressures (more like 275/75). Also, when I turn the rear A/C on, the front vents blow much warmer. I haven't measured them but I'd guess they're blowing around 50 degrees without rear A/C on and 65-70 degrees with rear A/C on. My question here is why? Can anyone offer any advice?

 

 

Again, this is my first official post but have been "lurking" for quite a while.

 

Thanks so much for your advice.

 

Darrell