I have a 2006 LR3 SE. I recently upgraded and got new tires, so for the first time in months the tire roar from by original Goodyears is gone and my vehical is actually quite enough to hear smaller rattles and other noises. I've recently started to notice a slight roar in the blower of the AC system when driving. You can hear it at idle, or when doing start and stop driving at low speeds before wind and tire noise drowns it out. It changes pitch along with the RPM of the engine, and seems to be gradually getting a bit louder over time. It's definitely the blower motor, as it stops when I turn off the AC system. It's almost like the RPM of the blower motor is changing a bit when the engine RPM rises or lowers and the alternator is charging more or less, thus affecting the power supply to the blower motor.

Its not a huge issue, but it does seem to be getting a bit worse and I'm close to the end of my warranty. Does anyone have a idea about what might be the issue?

 

If it is still under warranty, then take it in to the dealer. It will be covered. The warranty is there for a reason, so use it and save yourself some grief.

 

I've got the same deal. I didn't realize what it was until I read your post. They replace my rear differential last time in to try to fix the problem!!! Oh well, I'll need to get this fixed soon as my warranty runs out at the end of next month. Thanks!!!

 

Let me know if they are able to find the cause. Mine is in the shop right now, however of course they are "unable to duplicate the noise" (I believe there may be a screening process for LR mechanics that they have to have toured the country with Metallica and have lost most of their hearing before they are allowed to address customer issues with noises or rattles), so I doubt I'm going to get anywhere with it this trip and will probably have to wait until it gets so loud there is just no doubt whatsoever.

 

The blower whine change is becuase as the alternater spools up ( more rpm) the power to push the fan is increased so wella more noise. 2 quick questions is the fan cavitating becuase someone didnt replace the pollin filter??? and do you have alot of chipmonks around your house and possibly a bag of dogfood in your garage??? scott...

 

Turns out it's the compressor, not the blower. Took two trips to the dealer, but seem to have this one figured out. As typical, they did not have the parts needed in stock and they are on back order, but hopefully they will come in in a few more days and I'll get this one behind me.

 

The symptoms that rbelz describes seem identical to mine. I too am hearing a noise that sounds like the blower bearing is grinding or the fan blades are rubbing. It happens when the climate control is on (heating, but not sure about a/c cooling) but stops when the Econo button is switch on. The noise also changes with increased RPMs. The noise does not change when the blower speed is increased/decreased.

I assumed it was related to the blower motor, but the noise comes from the drivers side / center of the dash, not the passenger side. I quickly checked in the blower behind the glove box but did not find any debris.

I have recently had the A/C compressor changed, so I don't think the solution below is relevant to my issue.

Any help? Thanks

 

Usually this whine is from low refridgwerant or in my case the lubricating oil was low and needed to be added.

 

Thanks EastCoast I will get this looked into and share the results.

 

What he said.