2016 6 Speed FX4 80,000MI

Notice all the time with speeds over 45MPH when coasting and then reaccelerating you get a clunk in what feels like the drive shaft. Any ideas what could cause this? Or is it normal operation.

happens sometimes under slower speeds, and sometimes when accelerating from a stop.

the truck does have a 2” lift, maybe excessive angles?

 

I have a 2018 3.5 EB, 10 speed with 55,000 km on it and have noticed a similar clunk. Truck is stock height. Intermittent and happens usually at lower speeds when I have let off the throttle and then reengage.

 

2017 3.5 EB 32,000 miles same clunk.

 

2020 2.7/10speed and same clunk.

 

Universal joints most likely, I need to get mine checked (they clunk also) under the bumper to bumper mile warranty

 

Does it mostly happen straight line or during turns?

 

Same here. Every once in a while. (2019 XLT 5.0 24k miles).

 

Happens to me sometimes. It will happen when the driveline unloads. It's really noticable on slight declines but will do it on flat roads. I'm in a 2018 fx4 with 30k. It could be play​​​ in the t-case I'm guessing.

If it were u joints you would here more of a ping noise when you get back on the gas and possibly a squeak as it turns. It wouldn't be intermittent.

 

These drivelines have a lot of slop in them. If you get it just right like letting the gas off right before it changes gears you'll shake the whole truck with the clunk.

 

Same here on my truck. I notice it in town between stop signs when I come slowing to a stop it will sometimes clunk and then when i press the accelerator from a rolling stop it will clunk. I've had this problem since the truck was new, major annoyance but after 5 years, hasnt caused the truck any harm.
I took it to several dealerships who said there was nothing they could do. I eventually contacted the Better Business Bureau and filed a claim against the Ford dealership where I bought the truck. Ford got involved and sent a representative and also found nothing could be done. Ford settled the dispute with the BBB by offering me either a truck buyback or a free extended warranty, I took the extended drive-train warranty which was for an additional 2 years.
There are many threads on clunks in this forum, many of them offering fixes and suggestions that don't work or the threads get off-point. I believe it is too much slop somewhere in the drive train, but have not found any information that has pinned the problem down.