Loud clunk noise

[FordTechOne]

My 2019 doesn't exhibit any shifting issues unless I let off the accelerator pedal immediately after a shift. The resulting noise is the normal lash in the driveline reacting to the change in power flow.

As far as 2017 and 2018 models, a TSB was released to reprogram the PCM calibration to resolve a variety of issues. Here is the TSB, check your build date and go to your dealer if necessary:

TECHNICAL SERVICE BULLETIN 18-2274

2.7L/3.5L/5.0L Engine And 10R80 Transmission - Harsh/Bumpy Shift And/Or Engagement Concerns - Built On Or Before 15-May-2018
07 September 2018

Model:
Ford
2018 F-150

Issue: Some 2018 F-150 vehicles equipped with a 2.7L, 3.5L or 5.0L engine and 10R80 automatic transmission and built on or before 15-May 2018 may exhibit harsh/bumpy upshift, downshift and/or engagement concerns.

Action: Follow the Service Procedure steps to correct the condition.

Warranty Status: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage Warranty/ESP coverage limits/policies/prior approvals are not altered by a TSB. Warranty/ESP coverage limits are determined by the identified causal part and verified using the OASIS part coverage tool.

Description Operation No. Time
2018 F-150 2.7L/3.5L/5.0L: Reprogram The PCM (Do Not Use With Any Other Labor Operations) 182274A 0.3 Hrs.

 

[FordTechOne]

Sorry to hear..From what I have been reading, it sounds like some 10 speeds are doing what the 8 speeds are doing, it even looks like a class action started for the 10 speeds also. I know first hand about the 8 speed. It happens at random times right? If you make a gradual slow down to a stop it really doesn't happen. If you make a slight abrupt stop it happens right? That's what happens to my 8 speed. Here are the class actions. Is your's doing what it states? Remember GM and ford worked together on building the 10 speed.

https://www.classaction.org/gm-8-speed-transmission-defect-lawsuits

https://www.classaction.org/news/cl...ion-prone-to-shifting-harshly-and-erratically

Lawyers are scum, you can't assert that a problem is legitimate based on lawsuit because the lawyers will grasp at any straw they can until they get a payday. The 8 speed and 10 speeds are completely different unrelated transmissions with no shared design.

The reason that a noise can occur when you make an "abrupt" stop is that there is lash in the driveline by design. When you suddenly disengage power flow, the tolerance stack up between the input/turbine shaft at the transmission and the axle shaft splines at the differential will oscillate as power is removed. This is true on ANY vehicle with a RWD or 4WD powertrain and a manual transmission or locking torque converter. These components are designed to have make contact on the "drive" side or the "coast" side...not to oscillate due to a driver instantly changing the driveline load.

 

[McM]

Lawyers are scum, you can't assert that a problem is legitimate based on lawsuit because the lawyers will grasp at any straw they can until they get a payday. The 8 speed and 10 speeds are completely different unrelated transmissions with no shared design.

The reason that a noise can occur when you make an "abrupt" stop is that there is lash in the driveline by design. When you suddenly disengage power flow, the tolerance stack up between the input/turbine shaft at the transmission and the axle shaft splines at the differential will oscillate as power is removed. This is true on ANY vehicle with a RWD or 4WD powertrain and a manual transmission or locking torque converter. These components are designed to have make contact on the "drive" side or the "coast" side...not to oscillate due to a driver instantly changing the driveline load.

They may be different, just that there doing the same thing. I understand what you are saying. It makes sense to a point. As for all 4wd and rwd, I’m not sure. The lash you talk about is in my transmission. There is a lot of clanking going on in there, it's been verified. My dodge I had for 13 years never had the clanks or clunks. My wife’s Audi is smooth as silk. When I have people in my truck and they say to me “What was that ” there is a problem. There are 14 service bulletins about the 8 speed all pertaining to the shudder and clunk. GM knows about it, they just don’t know how to fix it. The class action was started by and individuals not by the lawyers. I don’t want to go back and forth. I’m just saying mine along with many others are having the same problem with the 8 speed and it’s not normal. They already did the fluid flush and changed my valve body.

 

[RiskTkr]

This thread is old, but I'll bring her back to life. After getting gas today (filled to the top) I was breaking at a stop light and booooom. I thought something was in my bed jumping around or my tire exploded. About 10 min later it happened again but much quieter.

Is this gas backfire in the exhaust or something to do with the trans? Who knows....

 

[thinkrevolutionx]

So i had something like this happen when I first got my truck (2018). I took it to the dealer because there was a software update for the 10 speeds at the time. Turns out that some bolt(s) in the transmission weren't properly torqued (possibly bellhousing? I don't recall to be honest) causing just the right amount of shift under specific circumstances. When I got it back, all was good and haven't had the issue since.

 

[Romes86]

Glad I was able to find this thread. I have a 2022 experiencing the exact same issues. Today, coming to a stop, a loud clunk was heard. It sounded just like how many of you have described as something slamming in the bed of the truck or tire exploding. This is the second time it’s happened and heard it a couple weeks ago when coming to an abrupt stop at a traffic light. I’m assuming no one knows for sure what the hell it is and I’m sure no dealer will get it to replicate since it happens so randomly. Anyways.. if anyone can add on to this I am curious as to what it could be. Me personally I don’t think it’s anything tranny related and leaning more towards a drive shaft issue.