RDU issue

[Leeford]

I have recently had this issue fixed myself. Somewhere around 60k miles i started hearing a clunk under acceleration, notably while turning, then it started to get louder and more prevalent. At first I was thinking it was my spare tire being loose in the storage compartment. Then I thought perhaps it was something underneath that was loose. Eventually I couldn't deny it was the RDU. so I took it in and the techs said that it was the RDU and they would be replacing it. So it sat for a couple of days while they waited for the part to come in. Then when the parts came in they said that they had to wait for another part to move the vent location. Eventually I was told that they did not actually replace the RDU they just serviced it and installed the vent relocation kit. So far no more noises or problems. However, I still wonder what damage actually occurred while the RDU was acting up internally. Seems that they opted to only replace the vent and service the RDU to save money rather than ensure it won't be a problem down the road.

Having the exact same issue with my 21 OB. Aug 1st for the appointment, Asked if I can still drive it and i got a vague, "its ok response". I clarified if this was going to cause any other issue s and they stated, "well if you get warning lights, let us know" lol.

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[RNM]

Having the exact same issue with my 21 OB. Aug 1st for the appointment, Asked if I can still drive it and i got a vague, "its ok response". I clarified if this was going to cause any other issue s and they stated, "well if you get warning lights, let us know" lol.

Yeah, that's a while off. If I had another vehicle I would just use it instead until you get it in the shop. But sometimes you gotta do what you gotta do. I waited for a month or so before it was getting really noticeable.

 

[Dude]

TSB 24-2386
TSB Date: 2024-11-18

Chatter/Shudder During Low Speed Turning Events

(supersedes TSB 24-2185 which supersedes TSB 23-2335)

Also see:
https://www.broncosportforum.com/forum/threads/tsb-24-2386-chatter-shudder-during-low-speed-turning-events.16524/post-260954

 

[Foghorn]

I have a 2022 BS/OBX, less than 20K miles. I had the RDU vent tube update done, and the tech put in fresh oil at 15K miles. Now I hear a slight thump and shudder when making a slow right hand turn. I took it to dealer, made sure the W/O described the noise and thump and shudder when turning, and the tech updated the PCM and BCM software to " latest level. " and sent me on my way. No discussion of a possible mechanical problem . I don't believe the tech even drove the car around the lot.
No surprise, the noise is still there.
I am unclear about which type of RDU responds to the friction modifier. As I understand it, my OBX and the other non-Badlands models have a single clutch RDU. The Badlands has a dual clutch RDU. Does the friction modifier work for both? I have seen somewhere that only the dual clutch RDU responds to this.

What should I do? The recent W/O clearly describes the problem. Do I go back to the dealer? Will the problem get worse? At the current rate, my power train warranty for 5 yrs will expire when I still only have around 30K miles on the vehicle. When my warranty is up, should I change the RDU fluid and add the friction modifier? Assuming the problem is not worse by then.

The thump and shudder is very hard to detect at this point. I can feel it because it is my car since new, and I know when something changes. A tech would likely say he can't feel anything wrong.

If you had a new RDU installed, what model do you drive? What was the condition that pushed the dealer into replacing the RDU? Error codes? Undriveable?

All suggestions welcome.
Fog

 

[Major Kong]

I have a 2022 BS/OBX, less than 20K miles. I had the RDU vent tube update done, and the tech put in fresh oil at 15K miles. Now I hear a slight thump and shudder when making a slow right hand turn. I took it to dealer, made sure the W/O described the noise and thump and shudder when turning, and the tech updated the PCM and BCM software to " latest level. " and sent me on my way. No discussion of a possible mechanical problem . I don't believe the tech even drove the car around the lot.
No surprise, the noise is still there.
I am unclear about which type of RDU responds to the friction modifier. As I understand it, my OBX and the other non-Badlands models have a single clutch RDU. The Badlands has a dual clutch RDU. Does the friction modifier work for both? I have seen somewhere that only the dual clutch RDU responds to this.

What should I do? The recent W/O clearly describes the problem. Do I go back to the dealer? Will the problem get worse? At the current rate, my power train warranty for 5 yrs will expire when I still only have around 30K miles on the vehicle. When my warranty is up, should I change the RDU fluid and add the friction modifier? Assuming the problem is not worse by then.

The thump and shudder is very hard to detect at this point. I can feel it because it is my car since new, and I know when something changes. A tech would likely say he can't feel anything wrong.

If you had a new RDU installed, what model do you drive? What was the condition that pushed the dealer into replacing the RDU? Error codes? Undriveable?

All suggestions welcome.
Fog

first item on the to-do-list
remove filler plug
insert pinky finger
check fluid level

 

[Dude]

@Foghorn I believe you are within the 60k powertrain warranty which covers repair/replacement of the failed RDU Components at no cost to you.

I would not put in friction modifier or do anything except schedule an appointment with the Ford dealership. They may want to charge you to do the diagnostic but that should be refunded if repairs covered under the powertrain warranty. Talk it over with the service advisor.

Have the service advisor and/or Tech ride along with you so you can demonstrate the issue. But if it’s not a repeatable problem where they can hear or feel the issue that’s more complicated.

 

[Dude]

Also… friction modifier for the RDU is in the class of a bandaid fix - you will want to do everything possible now while under the powertrain warranty including keeping good records and taking it in as many times as needed to the dealership to demonstrate the RDU issue

RDU repairs/replacement is expensive for you after the powertrain warranty has expired so you want that RDU fixed within the powertrain warranty

Ford wants to get you past the powertrain warranty period .. that’s why they stall with the vent hose and fluid replacement which does not fix a real RDU issue if that’s the problem with your RDU (you don’t know yet if you have a real issue until the dealership agrees - maybe consider going to a different dealership)

If the RDU issue gets worse after the powertrain warranty ends then you could consider other options like the friction modifier

Keeping excellent records including what the dealership does might help you down the road getting some compensation from Ford if the RDU does fail after the powertrain warranty ends

Another owners experience: https://www.broncosportforum.com/forum/threads/2021-bronco-sport-loud-clunking-noise-on-left-side-beneath-car.16243/post-262310

 

[Leeford]

Update: went to dealer, RDU to be replaced. Parts are the issue. Will call when available. Noise is getting progressively worse. Asked about the quick fix and they said that this might ot might not work. Skip the line and replace. Should be one day out of service. Under warranty.

 

[Foghorn]

Just got an appointment for dealer to replace shuddering grinding etc RDU. Dealer says he ordered and received a new RDU to install. And all the parts needed.
I asked how long this would take.
Ans. 4 hrs.
This suggests to me I am not getting a new RDU.
Has anyone had a new RDU installed in 4 hrs?
What exactly do you think I am getting? Fluid replacement and a bottle of friction modifier. ?
I had the vent tube upgrade done in Feb 2025, and that included new fluid.
BS is at 18K miles. Still under power train warranty for another 14 months. .
I have sinking feeling I am about to get hosed, big time.
I would ask dealer to show me the removed RDU, but I suspect he is ready for that and has a " demo " used RDU ready to show skeptical customers.
Fog

 

[Dude]

Just got an appointment for dealer to replace shuddering grinding etc RDU. Dealer says he ordered and received a new RDU to install. And all the parts needed.
I asked how long this would take.
Ans. 4 hrs.
This suggests to me I am not getting a new RDU.
Has anyone had a new RDU installed in 4 hrs?
What exactly do you think I am getting? Fluid replacement and a bottle of friction modifier. ?
I had the vent tube upgrade done in Feb 2025, and that included new fluid.
BS is at 18K miles. Still under power train warranty for another 14 months. .
I have sinking feeling I am about to get hosed, big time.
I would ask dealer to show me the removed RDU, but I suspect he is ready for that and has a " demo " used RDU ready to show skeptical customers.
Fog

Perhaps you are getting TSB 25-2351, probably worth calling the dealership to verify exactly whst they will be doing in those 4 hours.

https://www.broncosportforum.com/forum/threads/new-tsb-25-2351-rdu-technical-service-bulletin-chatter-shudder-during-low-speed-turning-events.16807/

 

[cprcubed]

Put a couple of punch marks on the case. If they are still there after replacement, you know they didn't change it. Cheers!

 

[Foghorn]

I am only dealing with the " service advisor " who insists I am getting a new RDU. I asked what the book repair time was and was told " there isn't one for that job ".
I Googled the ? and an AI answer said 4-7 hrs if nothing goes wrong, all the parts are there and the service tech is the best guy employed by any Ford dealer anywhere in the world.
Whatever work they do is covered by the warranty, so I can't really press them. I guess the final verdict will be what the W/O shows in terms of parts used. I doubt the dealer will show a W/O that shows a new RDU was installed if that wasn't done. But do W/O for warranty work show details like parts used? Maybe what I get will just show " fixed as needed ".
My wife and I have already decided to dump the car as soon as we can.
Fog

 

[Dude]

I am only dealing with the " service advisor " who insists I am getting a new RDU. I asked what the book repair time was and was told " there isn't one for that job ".
I Googled the ? and an AI answer said 4-7 hrs if nothing goes wrong, all the parts are there and the service tech is the best guy employed by any Ford dealer anywhere in the world.
Whatever work they do is covered by the warranty, so I can't really press them. I guess the final verdict will be what the W/O shows in terms of parts used. I doubt the dealer will show a W/O that shows a new RDU was installed if that wasn't done. But do W/O for warranty work show details like parts used? Maybe what I get will just show " fixed as needed ".
My wife and I have already decided to dump the car as soon as we can.
Fog

Dealership will have a stack of papers after repairs are done containing full details but you’ll be handed your copy which is a subset. Ask to see the full info on the repairs and take pics.

 

[roboto65]

Well just noticed this today wife in the car also sounds and feels like the rear end is skipping or like a locker that is locked all the time when you turn. Have an appt in the morning.

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