2008 Ford Expedition - Thumping Sound

[tvlunn]

I have a 2008 Ford Expedition Eddie Bauer with electronic front and rear climate control.

The thumping sound I'm experiencing is periodically coming from the rear panel on the passenger side of the truck.

If I switch OFF the climate control, the thumping sound will cease completely.

I'm assuming there is an actuator of some type inside the panel that is failing which is causing the thumping sound.

Is there anyone on this site that has experienced this sound in the past and can identify the likely problem?

Thanks so very much!

 

[sjwelds]

There are actually two actuators back there. A very very common issue. I actually opened mine up and replaced just the gears. They were stripped.

 

[tvlunn]

Thanks sjwelds!

I called the parts store to get a price. He stated his book only listed ONE actuator, but stated if there were two inside the housing, the same actuator was likely used in both applications.

Does anyone know if this is a true statement?

Otherwise, I guess I need to take a peek inside before I place an order so that I get the correct part.

 

[aagitch]

I think there would be two. One to adjust temp and the other for directional (overhead/foot)

 

[Plati]

Search YouTube. Plenty of video's. Search this Forum also

Ford Tech Makuloco has good video where his dog helps him.

You can also look up part and buy on Rockauto.

What I did for long time was put on rear control and adjust Temp until thumping stopped. But that was for temp blend. When flow one started I just reached in and unplugged since I didn't need it.

 

[762mm]

Fords have been having this problem forever, it seems. It was the reason why I was always paranoid about changing blower temperature on my 99 Explorer... Crown Victorias and all other Fords had the same damn problem at the time. Still do, apparently...

It's called a "blend door actuator" and it regulates the amount of cold / hot air blowing in. Based on what I've read and seen on YouTube, the Expedition has one for the front and one for the back (hooray for multiple "climate zones" in a 14' x 6' box, lol!). And yes, they are prone to failure on Expeditions as well... because apparently making a small gearbox tied to a tiny electric motor is beyond rocket science for Ford engineers!

When they fail, they make a clicking noise. The other symptom is that the air temperature will not change regardless of where you set it.

 

[Plati]

2 in the back. One for temperature and one for air flow diversion. I had my hands on both. Unplugged both. 2003 XLT

 

[RenegadeBad_Dog]

Funny you this thread popped up because our 2016 is doing the exact same thing. Luckily I Googled it a while back and figured out what it was. It's for the temperature control I'm not to worried about it though figured I'll just replace it when it goes.

Sent from my SM-G973U using Tapatalk

 

[tvlunn]

Yep, it was broken gear inside the actuator. I went ahead and ordered a new actuator.

Anyone know if you can order a gear set for the units? That would be an easy AND cheap fix!

 

[Jst ROM]

To OP:

I have a 2008 Ford Expy Limited with dual climate controller and yes it's your "rear HVAC temperature blend actuator", you only have one in the back and one behind the front radio too. The part you are looking for is Motorcraft YH1856 Motor it cost about $50.00 on Amazon. You can do it yourself here's a great video from FordTechMakuloco on YouTube to install it.


Good Luck