Hi everyone,

New to this forum since upgrading from a '21 F150 5.0STX 4WD/Offroad to a '25 F250 7.3STX 4WD/Offroad in late July this year. Sorry if this has been asked - I did search this sub-Forum before posting but no hits were returned.

Is it normal or has anyone else experienced difficult acceleration accompanied by some disturbing grinding noise from what seems like either the differential or maybe the transfer case when they shift from reverse to forward or vice-versa on a hill? I have experienced this a few times now. The last time was on only a slight incline today in my driveway where the sound was mild compared to when it recently happened on a steeper incline earlier this week. I'm pretty sure (but could be wrong) that it isn't the transmission, which shifts very smoothly and feels much nicer than the '21 F150 I traded.
**The several times this has happened, I have checked and can confirm the differential lock was not engaged and neither 4WD mode was engaged.
The truck currently has ~2200 mi on the odo.

I called a local dealership and the service tech claimed his 7.3 F250 does it too and agreed it's strange but didn't seem worried - however, in my ~50 years of vehicle ownership, grinding noises never equated to anything good or normal.

Thanks in advance for any thoughts, suggestions or advice,
Phil

 

2025

use your warranty..get it checked out.

 

Roger that. I just wanted to probe other owners to see what they are reporting for both a reality check and to validate my concerns with the dealer. If no one else is reporting it, then it isn't "normal".

Thanks for responding.

 

Whining noise coming from the rear differential on our '23 250 pulling our 5th wheel turned out to be big. With only 6K on the truck Ford ended up replacing all of the inards. Believed to be some kind of casting contamination. Thank the Lord it was under warranty!

 

Thanks. I'm hearing more of a grinding than a whining noise but maybe that's subjective on my part. I appreciate your response. Thank you!

 

FIL had a '22 F250 with the 7.3. Going from reverse to drive would occasionally be accompanied by a squeal/grinding noise from about 5k miles until he traded it in on his '23. Never could get it figured out, techs could make it do it but couldn't locate anything wrong. Fluids looked good, no unusual wear, nothing.

Those trucks just seem to have something going on. It doesn't seem to affect their driveability, but it absolutely is worrisome.

 

OP - You said, "difficult acceleration accompanied by some disturbing grinding noise". Difficult acceleration? Does this and the noise occur just for a second as you begin to move while on an incline after holding the brake? I'm wondering if it is one of the auto E-brake functions.

 

Ford8502 - That is a very relevant point. In fact, it had crossed my mind but I didn't want to make my original post too long. The reason I lowered it on my list of possibilities is because it isn't just for a moment when starting but lasts 1-2 seconds through acceleration. That said, the effort and extra gas pedal effort to get moving could be something related to an auto E-brake application. Why is that a thing?! lol
For sure, the E-brake light isn't on though - but for anyone who has lightly dragged a brake at a stop sign, the sounds are similar.
Can the auto-engage be turned off in the settings?
Thanks for your post!

 

Sounds like, after re-reading your description and this added info, it could be the 'hill start assist' that they're putting on vehicles today...that I don't think is truly necessary for vehicles with automatics. The idea behind it, from my understanding, is that it helps keep your vehicle from 'rolling back' on a hill, or holds you in place a bit while engine RPMs climb higher into the power band. Neither of which has ever been a problem for me in an automatic-equipped vehicle, but COULD be an issue for a novice manual-equipped vehicle, of which there are very few today.

There MAY be a way to turn it off in the settings in the radio, I seem to remember seeing it on one of our vehicles but I can't tell you which one, or if we even still own said vehicle.

 

99powerstrokedF250: I'm chuckling right now because my search of E-brakes (after Ford8502's post) sent me down a rabbit hole that lead to Hill Start Assist. Feeling pretty sure it's one of these two. I thought HSA was On/Off by the driver but I'll check on it and report back here eventually.

The thing that's weird is that all these features existed on my '21 F150 and the truck never did it in my 3+ years of ownership. 🤷‍♂️

This is a great group - thanks to all for your posts, comments and suggestions!

 

Heck my 2013 has hill start assist and it’s been completely trouble free.

 

I seem to have identified the culprit of the concerns expressed in my OP. The great suggestions here prompted me to poke through the settings menu when I stumbled on "Reverse Brake Assist" before finding "Hill Start Assist." I saw that RBA was "On" so I turned it off and (being sure to test only one change at a time) repeated the steps leading to my concern. The process associated with the grinding sound has been: come up a slight hill, stop, reverse and back up a bit, stop, shift back to drive to, then try to accelerate forwards. The "grinding" noise I was hearing when trying to accelerate after shifting back to drive appears to have been cause by electronic brakes applied when I reverse. I thought the RBA was only supposed to engage if an obstacle was detected when backing up. I'm not happy about how it performs but glad I found the cause and that it's as simple as disengaging a tool for something every driver should be attentive about without assistance.

Thanks to all who chimed in and for the sanity check, I'd be interested if others can associate the behavior I described with their RBA. This never happened on my F150, which also had RBA, though maybe it was never active(?).

Cheers,
Phil

 

RBA is more robust in Super Duties (it is a much heavier vehicle), so it makes a bit more noise. I have had mine activate every now and then when not trying to hitch up to a trailer, and...at first I didn't like it but now that I'm used to it, it does make hitching up a bit easier because I don't have to anticipate the 'roll.' When I first got it though...man did I look like a fool, stopping short, going too far, just for the truck to set the e-brake and NOT move like I was used to.

Looking back that probably WAS the issue my FIL had with his '22.

 

Yep, my F150 would roll a short mile when trying to hitch up my RV. I got myself in the habit of engaging the Ebrake to stop it. I suspect I'll do the same with the F250. We're planning our first tow for late October.

 

Hey there! Welcome to the community. We'd like to learn more about this situation and have sent over a private message. Feel free to reply at your earliest convenience.