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Andy4639 · 04-20-2020, 09:06 AM

If you are wanting a 100% AC to work good then I would leave it. That ensures the hot water doesn't come into the cab while the AC is on. Most people put it in the other line though. If the vacuum operated valve leaks hot water by then your AC will never get as cold as it should inside the cab. Putting it in the other line makes sure it doesn't circulate at all through the heater core.
If you do decide to take it out a simple test is to feel the lower part of the interior heater box to see if it is warm when the AC is on and the truck is sitting still. If it is some what warm then you have water leaking by the vacuum valve and you will not get the cab as cool as it could be.

04-20-2020, 09:06 AM	#8
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,945	Re: A/C Question If you are wanting a 100% AC to work good then I would leave it. That ensures the hot water doesn't come into the cab while the AC is on. Most people put it in the other line though. If the vacuum operated valve leaks hot water by then your AC will never get as cold as it should inside the cab. Putting it in the other line makes sure it doesn't circulate at all through the heater core. If you do decide to take it out a simple test is to feel the lower part of the interior heater box to see if it is warm when the AC is on and the truck is sitting still. If it is some what warm then you have water leaking by the vacuum valve and you will not get the cab as cool as it could be. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.