It's the starter bendix retracting after the engine starts. I hear it on m '15 if I start it with the door open.

 

I guess you didnt see the video of the driveshaft trying to turn?

 

I see what you're saying about putting it in park first, but that means that the transmission is allowing the engine torque to be passed to the drive shaft when the gear selector is in Park. I dont feel that this is normal, and out of the 4 trucks with automatic transmissions that I've owned since 2001 (3 of them Fords), this is the only one to make this noise on startup. This is also the first generation of the 10 speed transmission. Your statement does make me curious, if I put the truck in Neutral before starting it, would it do the same? I'll try this today.

 

So here are my observations for today. If the truck rests on the transmission, the clunk is not as pronounced, but it does still happen and if you watch the driveshaft, it does jerk a little with every start of the engine. I will probably take it to a 3rd dealership to show them the issue and get their thoughts on the issue.

 

Very interested as mine is doing the same. Mine is also the 2017 3.5 eco 10 speed. I only notice it every few starts, but it definitely sounds like it’s drive train related.

 

Wonder if one of the clutch packs isn't releasing enough when it's cold.. Does the truck move if in neutral when cold and on a level surface?

 

Why wouldn't all F150 trucks with 10 speeds exhibit the same noise/clunk? Is this issue only in some 10 speeds or is it a systemic problem and simply not noticed/reported by most OP's?

 

For me it seems that it is not related to the temperature - it was doing it when it was very hot outside and with both cold and warm engine. And I was thinking about the level surface but, again, I heard it on my driveway that is slightly inclined towards the street (the front part of the vehicle) and on the flat street surface as well.

I could not find (yet) a single factor that would correlate with this clunking noise.

 

Guys, if you havnt already, please try taking a video of your drive shaft clunking like I did in the video below. I recvd a call from Ford yesterday, they setup a meeting with an onsite engineer next Tuesday to look at the truck, and I sent them the video as well. if yours is doing the same thing post the video here or post a link to youtube if you post it there. The more we can show them having the issue the better.

https://www.f150forum.com/f118/singl...4/#post5492570

 

So I met with the Ford engineer. When I arrived at the dealership, they had my truck and another new 2017 ecoboost from the lot on the rack. The new 2017 did the same noise, and with the trucks in the air, it was easy to tell that the noise is coming from the transfer case. On the new 2017, the driveshaft did move on one of the engine starts he did on that truck. So in the end, its a "characteristic" of the truck. He didnt say it was normal, but since a new one from the lot does it, its currently listed as a "characteristic". What i asked him to find out was WHY the transfer case makes that noise, and he said he would send some mails to see what he could find out. Thats it for now.