Whine / groan coming from cargo area
 

At first I thought it was coming from under the hood and might be a belt, but recently I've had the seats folded down and it appears to be coming from the cargo area. I only get it sporadically, only with MAX AC on and either at a stop or slowly accelerating. Its a odd sound like moaning/whining metallic sound. No service lights and no other symptoms. I was thinking its got to be related to the battery AC somehow?

Any thoughts? Couldn't find anything on search. Thought about the blend door but everyone else seems to get "the wrench". Maybe mine is failing but still works?

Re: Whine / groan coming from cargo area
 

That sounds like the groan/squeak I get from the rear hatch area. I haven't bothered to track it down yet, but I believe it's coming from the latch on the liftgate or rear window. There was a thread about this, https://www.greenhybrid.com/discuss/...r-hatch-18634/ . Like I said though, mine is a groan/squeak, not a rattle.

Re: Whine / groan coming from cargo area
 

No, its not a rattle. I already had that problem "fixed". This is a metallic whine....like metal rubbing on metal at speed. That's why I first thought it was a belt pulley or something like that.

Re: Whine / groan coming from cargo area
 

Possibilities: brakes, driveline, A/C orifice noise for Traction Battery A/C.

Drive next to a barrier on the sides with your windows down and listen for the noise to be reflected off the barrier back to you. See if you can do one side and then the other. If its driveline or brakes you'll hear both the inside noise and a reflected noise off the barrier.

If not then look more closely at the A/c system. As I recall there is an orifice back there and these sometimes make noises as the freon is flowing thru them. Supposed to be designed to prevent this but things can happen. See if you can correlate the noise to Traction battery Cooling cycling on & off.

If driveline it might be u-joints starting to go bad-an easy fix; or it might me the CV joints from the differential to the wheels-a more complicated fix.

Brakes: the rear brakes are drum-in-hat type brakes. The parking brake is a drum type. If it's not letting go completely then it could be the culprit. Or it could be a disc brake pad issue, they can make such noises.

Re: Whine / groan coming from cargo area
 

its definitely AC related. It ONLY happens when I have it set on MAX AC and the noise stops as soon as I switch to regular AC. I guess I'll be taking her in...

Re: Whine / groan coming from cargo area
 

Bill - you may want to clarify this section. Sounds like some conflicting information for a 2006 model. Actually, sounds like its not the brakes anyways.

Re: Whine / groan coming from cargo area
 

glennb: are you familiar with drum-in-hat brakes? They use a drum type brake system (with shoes) for the parking brake system, while using disc type brakes for the actual vehicle braking. I don't like this system at all, but it brings in two different failure modes if brakes are involved.

I agree it doesn't sound like brakes. I was just giving some thoughts as to how to identify the problem area.

Re: Whine / groan coming from cargo area
 

There was a TSB back a few years ago about the parking brake shoes not centering when released cause a noise but I don't remember what year. I think there was another thread here that it was mentioned in.

Re: Whine / groan coming from cargo area
 

The rear brakes on the 2006 are disc brakes - pure and simple. "Drum in hat" term only applies to the parking brake.............could be splitting hairs, thought your initial reply was a little confusing. See the attached description from Ford.

Re: Whine / groan coming from cargo area
 

glennb: What was it I said above? drums for the parking brakes and discs for the vehicle braking?

You're being unnecessarily picky and you know it. To a person knowledgeable of what drum in hat means, my answer was clear. A person that didn't understand the design would have asked. So why did you make that point again?

My point was simple: there are two modes of potential problems in the rear brakes because of the drum in hat design. EG: see wptski's entry about a TSB of a few years ago for the parking brakes.