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  1. #1

    Default heater and/or ac lines inside body

    I can't figure this out! My 2003 Suburban Z71 with 104,000 miles always drips large amounts of condensate, but it SOMETIMES contains something oily. The constant drips come from inside the body cavity after the pass. side front wheel. The ac and heater hoses for some reason go through this area before coming out along the frame. I can't gain acess to this area to view the problem. I am not losing any coolant, nor is my motor oil contaminated. What could be oily in the condensate and why would the condensate drip from inside the body. The inside of the truck is dry everywhere. I dred bringing it to the dealer to begin replacing items until the problem is found. I appreciate any and all help. Thank You

  2. #2


    I wouldn't be surprised if an auto trans leak, engine oil leak or other oily leak is dripping down and along the line... it might not be coming from the line itself. Follow the line all the way up and see what's up.
    I like you.

  3. #3


    Last night the dripping only happened when the ac was on. The fluid is mostly water with an oily feel to it. Could it be refrigerant ? My ac is blowing very cold. I wish I could find a way to see into the area where GM ran the lines and hoses on their way to the rail from the engine compartment. At this point, if there is a leaking line inside, I can't see it. I don't know how a new line can be installed inside this area.

  4. #4


    If it were leaking that much oil from your a/c system, you wouldn't be blowing cold anymore! A normal automotive a/c only hold 4-8 ounces of PAG oil total, and most of it will pool in the compressor and condenser. My guess is that oil got onto the line from somewhere else. Then, the condensation (water) that forms when you run the a/c is mixing with this water and they are dripping together.

  5. #5


    Can oil get into a refrigerant line other than the refrigerant oil ? Does anyone know where a 2003 suburban 1500 Z71 condensate should be dripping ? It seems so wrong for the constant large amount of condensate to be dripping from the body and not a hose or drain. Thank you for the help thus far. Without this club as a resource, I guess some of us would be at the mercy of trial and error.

  6. #6


    not sure about the oil, but the condenser does have a drain and if the drain is plugged the water has to go someplace...

    I would locate the drain and make sure its open

  7. #7


    That's my problem. I don't know where the evaporator drain is. I may go to Chevy and ask.
    Thanks for the response.

  8. #8


    well just get under there and look! its probably going to be a rubber hose dangling down some place. I doubt they will tell you.

    you could also take your glove box/trim off and poke around a bit.

  9. #9


    I have looked everywhere under this vehicle. For all who may read this, I think I have found the drain. If you feel behind the accumulator, (impossible to see), a pipe comes out of the firewall with a 90 degree rubber end. This must be the drain. I'll try to get something flexible to work around and behind the accumulator to clean it out. What a bad location. I hope this post was helpfull.

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