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rear locking diff operation.

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Old Jan 5, 2023 | 04:06 PM
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rear locking diff operation.

I tried searching but couldn't find the answer; For those of you with a locking rear differential, can you engage it at speed (F-150's used to be under 20mph) or do you need to be stopped?

Thanks,
Dave

 
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Old Jan 5, 2023 | 04:21 PM
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Can be enganged under 20 at speed, automatically disengages over 20.
 
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Old Jan 5, 2023 | 04:35 PM
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From: Lost in the Ozone....
Page 237-238 of the 2022 Owner's Manual:

You can activate the differential electronically and shift it on the fly within the operating speed range. The electronic differential will disengage when the vehicle speed exceeds a set value and it will reengage when the vehicle speed goes below a set value.


 
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Old Jan 5, 2023 | 04:37 PM
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Thanks guys; that's what I thought. The GM guys on another site were suggesting the Superduty needed to be stopped to engage the locker. As my M300 is a limited slip, I wasn't sure.

Dave
 
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Old Jan 5, 2023 | 07:24 PM
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Who's going 60mph in 4Lo???
 
Old Jan 5, 2023 | 08:14 PM
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Originally Posted by Chingon
Who's going 60mph in 4Lo???
laughed at that one as well.
 
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Old Jan 5, 2023 | 08:29 PM
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Originally Posted by MrTnT
laughed at that one as well.
When stuck and spinning
 
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Old Jan 5, 2023 | 09:51 PM
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Originally Posted by Chingon
Who's going 60mph in 4Lo???
Wheel speed not actual vehicle mph or the dealership lot boy taking your $90k truck out for lunch with his buddies for beers and smoking 4 wheel burnouts.
 
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Old Jan 6, 2023 | 08:35 AM
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I put a SPE Full Lock Diff Kit on my 2014 F150 4x4 and it worked great. I could engage and disengage anytime or speed. Only problem was that it worked in reverse with the dash ****. I would have to push it in to engage and the dash screen 4x4 icon did not show when engaged. SPE hasn't made a kit for the 2021 F250 or else I would have it again.
Always worked flawlessly in the F150.
 
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Old Jan 6, 2023 | 09:02 AM
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Originally Posted by meaz93
I put a SPE Full Lock Diff Kit on my 2014 F150 4x4 and it worked great. I could engage and disengage anytime or speed. Only problem was that it worked in reverse with the dash ****. I would have to push it in to engage and the dash screen 4x4 icon did not show when engaged. SPE hasn't made a kit for the 2021 F250 or else I would have it again.
Always worked flawlessly in the F150.
with the torque and light rear weight on these trucks that would be so fun and an absolute tire destroyer lol
 
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Old Jan 6, 2023 | 09:06 AM
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I put the SPE kit on my 19 Superduty, it works as it should with exception of the light. Pull to engage & push to disengage.
 
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