A PITA, do you have AC service tools to recover the refrigerant? If you need some manuals pm me your e-mail address.

You will need the proper amount of the proper type of oil, the refrigerant, and refrigerant tools (gauges, hoses, etc). Compressor (blow out the lines), the seals for your leaky joints (or a new line). and so on..

If you do not have that stuff, it might be better to take your parts and truck into a shop that does have the right equipment, ie: most shops.

 

Alright, sorry to keep this one going, but the original poster described exactly what I'm hearing in my LR3 now. Whenever I have the A/C on (confirmed by hitting the Econ button to shut it off) I get a low hum or whine that changes with engine revs. Sounds a lot like a bad bearing and I originally thought it was a tensioner pulley going. Having isolated it to the A/C system, do I try recharging and checking for leaks or should I just replace the compressor? I have an auto stethoscope but from what I can see, it's too far down for me to reach while the engine is running.

 

Mine has had a similar whine for a year now. I would like the replace the AC compressor, but it is still cooling. You could have it pressure checked, sometimes AC makes noise if low, but sounds like a similar situation as mine.

 

That hum or sometimes whine , that changes with engine revs, is your system low in refrigerant. You most likely have a leak or leaks on the pipe connection joints under the car. I had that hum for a long time , but decided to take it to a local dealer as I already new I had leaks on there connectors down there. I discovered them a few months a go while changing engine oil. I always go thru entire chassis and do a monthly check up .It turned out I was low on refrigerant an entire pound . My AC system contains 900 g, which is 2 pounds , so that is why my AC still worked, but not as quite as frigid as it use to be . I was not ready for a pipe overhaul as it is very expensive , so decided to refill the system and all is still silent and works well so far.I worry about pipes when spring comes.I will probably blank a rear AC system altogether .I don't have a need for it.

 

I have an LR4 that is humming from the passenger side when I turn settings to LO on the A/C ****. Started happening after i change the cabin filter above the blower motor. Do i need a blower now?

 

is the filter installed right...? My hum or noise was under the hood when AC was running. I did replace the AC pump to resolve that one. Check your cowl above the cabin air intake for warping. Did your old filter show signs of having been wet?

Not clear based on your description of what your problem is. If it started when changing filter maybe it's interfering with the fan.

 

It is coming from the blower for certain. The LO setting kicks it into high speed. It is a good humming,buzzing slight vibration type noise. When I dial back the speed it settles down a bit. Does so with filter or without. Was not doing this prior to filter change.

 

Something that was caught in the filter or settled on top of the filter probably just fell down into the blower motor when you changed the filter. I would just drop the motor (pretty simple... instructions are on this site w/a search) and look to see if a piece of tape or a leaf or something fell down in the fan blades. You might even be able to look from above with the filter out and a flashlight.

 

I will take a look at it. Thank you.

 

In my case its the blower motor bearings starting to go. I replaced mine with a very cheap option from Rock auto if I remember right it was under $40.