Jerking when switching drive modes

[mrimsofly]

Has anyone experienced this issue before ? When switching drive modes ( mainly in slippery, deep sand & snow) the truck jerks a lot when it goes forward and turns.

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[dolsen]

It happens only when switching drive modes or does it happen over and over when in those drive modes?

 

[mrimsofly]

It happens only when switching drive modes or does it happen over and over when in those drive modes?

It happens over and over when I’m in the drive modes

 

[dolsen]

Never heard of that and has not happened on my own truck. I thought you were saying if happens when specifically when switching drive modes.

ever try resetting the transmission adaptive learning tables?

 

[mrimsofly]

Never heard of that and has not happened on my own truck. I thought you were saying if happens when specifically when switching drive modes.

ever try resetting the transmission adaptive learning tables?

I did not..will have my pops try that next time he’s over my way

 

[Tomatoboy]

Which 4x4 mode status icon is displayed (4A, 4H, etc), and is it possible you are bumping the rear locker button when changing modes? IIRC sand mode switches to 4H, so I suppose it’s possible it isn’t dropping back out of that.

 

[mrimsofly]

Which modes specifically, which 4x4 mode status icon is displayed (4A, 4H, etc), and is it possible you are bumping the rear locker button when changing modes?

I don’t think I am and it would display 4A

 

[SumGuy]

Isn’t deep sand mode 4lo with the rear diff locked?

sounds like a locked rear diff - given the limited info given.

 

[Tomatoboy]

I don’t think I am and it would display 4A

Sand mode shouldn’t display 4A. Switch to the driver assistance page with power distribution and observe what it’s doing in each drive mode, see if it gives you a hint as to what’s engaging. The sensation you are experiencing sounds like binding somewhere, either due to being in 4H/4L or due to the rear locker being engaged.

 

[Sneezy]

I know for mine (an XL with no 4A and no e-locking diff) mine clunks when shifting into 4H if the truck isn’t stationary. In slippery mode mine shifts into 4H, I’m not sure if the 4A equipped transfer cases do the same, or if they shift into 4A instead. Either way it will clunk when I shift into slippery mode as well since mine is shifting into 4H. It’s done it since the first time I engaged 4WD and I have just over 12k miles now.

For reference the only time I shifted into slippery mode was when I first got the truck and it was wet so I was trying out the different drive modes. Which I know you’re not supposed to shift into 4H on a high traction surface, but my previous Ford (22 Maverick) said in the owners manual that slippery mode can be used on wet roads. However since Ford put most of the owners manual for the F150 on the center screen, which isn’t very intuitive, I experimented without reading the instructions first like all men do and tried it on a wet road like with the Maverick.

However when driving through snow mine will still clunk when shifting into 4H if the truck is moving even though it’s obviously not a high traction surface. Which is odd since the owners manual states you can shift on the fly. I just figured since it’s always clunked since I drove it off the lot that they were supposed to clunk, but maybe mine has never operated correct

 

[Tomatoboy]

I know for mine (an XL with no 4A and no e-locking diff) mine clunks when shifting into 4H if the truck isn’t stationary. In slippery mode mine shifts into 4H, I’m not sure if the 4A equipped transfer cases do the same, or if they shift into 4A instead. Either way it will clunk when I shift into slippery mode as well since mine is shifting into 4H. It’s done it since the first time I engaged 4WD and I have just over 12k miles now.

For reference the only time I shifted into slippery mode was when I first got the truck and it was wet so I was trying out the different drive modes. Which I know you’re not supposed to shift into 4H on a high traction surface, but my previous Ford (22 Maverick) said in the owners manual that slippery mode can be used on wet roads. However since Ford put most of the owners manual for the F150 on the center screen, which isn’t very intuitive, I experimented without reading the instructions first like all men do and tried it on a wet road like with the Maverick.

However when driving through snow mine will still clunk when shifting into 4H if the truck is moving even though it’s obviously not a high traction surface. Which is odd since the owners manual states you can shift on the fly. I just figured since it’s always clunked since I drove it off the lot that they were supposed to clunk, but maybe mine has never operated correct

My Lariat goes into 4A for slippery. The only time I feel a clunk outside of driveline binding is when the transfer case shifts in and out of 4L, as the changing between 2H/4A/4H modes don’t involve an actual shift on the 4A case.

 

[mrimsofly]

Yea sorry but this my first time with a truck. I came over from a Camaro so this is some what new to me

 

[Sneezy]

My Lariat goes into 4A for slippery. The only time I feel a clunk outside of driveline binding is when the transfer case shifts in and out of 4L, as the changing between 2H/4A/4H modes don’t involve an actual shift on the 4A case.

I wonder if it has something to do with the difference between the 4A transfer cases versus non-4A. I thought I read somewhere that the 4A transfer cases use clutch’s to engage whereas the non-4A’s use a shift fork. I could be wrong though as my memory isn’t always reliable

Either that or there’s a handful out there that are clunky (like mine) when they aren’t supposed to be

Edit: Thank you for confirming though that 4A equipped transfer cases use 4A in slippery mode!

 

[Tomatoboy]

I wonder if it has something to do with the difference between the 4A transfer cases versus non-4A. I thought I read somewhere that the 4A transfer cases use clutch’s to engage whereas the non-4A’s use a shift fork. I could be wrong though as my memory isn’t always reliable

Either that or there’s a handful out there that are clunky (like mine) when they aren’t supposed to be

Edit: Thank you for confirming though that 4A equipped transfer cases use 4A in slippery mode!

Correct, the 4A transfer case in the Lariat and above (excluding the Raptor and some Tremors with the Hi-Lock transfer case) only switches between 2H, 4A, and 4H by varying clutch pressure. 2H is the clutch fully open and thus disengaging the front wheels, 4H is the clutch fully closed (actually 97% closed, for some arcane reason) and so the front wheels are locked to the rears which will result in driveline binding, and 4A varies clutch pressure like any other electronically actuated clutch pack based AWD system to achieve AWD with no binding. The only actual shift that occurs is when 4L is engaged or disengaged, since that requires changing the gear set in the transfer case, and when the transfer case is disengaged for flat towing.

So with OP’s Lariat, the only clunks they should feel during mode changes are moving in or out of modes that use 4L. Other clunks would likely be driveline binding from using 4H or 4L on pavement, or rear end binding from using the rear locker on pavement. My guess is OP tested their modes on dry pavement and experienced driveline binding. (Reminder: you cannot use 4H or 4L on dry pavement, but you can safely use 4A on dry pavement)

(Note: you may still infrequently hear a clunk here or there when not changing modes. I have personally noticed in 4A that my Lariat occasionally balks at low-speed uphill turns on dry pavement, giving a little clunk, which I attribute to the system probably getting confused about how much torque to distribute to which axle and rapidly opening or closing the clutch.)

 

[Ford Motor Company]

Has anyone experienced this issue before ? When switching drive modes ( mainly in slippery, deep sand & snow) the truck jerks a lot when it goes forward and turns.

Hi there. Can you send us a DM with your VIN and dealership info? I can look into this for you.

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