Clunk when slowing down

[TD5-90]

I occasionally get a clunk if breaking hard and turning hard right. Only doing around 20 mph when I have experienced this noise.

I recently had mine in for service, and they said that this behaviour is known and related to the steering rod problem (sorry, German). No solution.

 

[SCVGrenny]

They did. Their conclusion was that they could not duplicate the issue.

I have the same issue—a "clunk" noise when shifting from 3rd to 2nd gear. I own a 2025 Belstaff with 1,700 miles. I started noticing the noise shortly after the steering stabilizer was installed, just two weeks after I purchased the vehicle. I wonder if those with completely stock cars are experiencing no issues. I have an appointment scheduled for December 22 at the Runsak dealer in Pasadena. If they determine that the problem is inconclusive, at least there will be a record of my visit.

 

[C-Mack]

Most likely the clunk noise is going to vary by vehicle and driving style somewhat (rapid throttle or brake inputs, etc…). Considering the large amount of rotational mass across the entire driveline coupled with the stack of tolerances through the axles, diffs, driveshafts and transfer case which could create enough slack to get the clunk/thunk noise on a downshift as the driveline goes from loaded to unloaded and back between shifts.

I experienced the same issue especially within the first 1,500 miles of driving my Grenadier from new. It seems like some software adaptation by the transmission has occurred as I’ve added more miles but the clunks are still happening but far less frequently and much softer when they do occur. I will certainly bring it up with the dealer but unless this is can be helped with further transmission software updates to soften the downshifts I don’t see this as an issue which will ever totally be resolved. As additional wear and tolerances build up within the driveline it could even get worse as mileage builds.

Sometimes with robustness you have to sacrifice a little bit of refinement but you’d think nowadays that should be easier to achieve. The whole clunk issue reminds me of driving old Land Rovers with spline wear on transfer case input shafts and the like, you sort of end up driving around the issue to keep things as quiet as possible. It’ll be interesting to watch and see if IA recommends any software or hardware changes to address the issue but I really don’t see that happening in a broad sense but more on a per-customer basis based on complaints.

 

[abbeyroad]

I experienced the same issue especially within the first 1,500 miles of driving my Grenadier from new. It seems like some software adaptation by the transmission has occurred as I’ve added more miles but the clunks are still happening but far less frequently and much softer when they do occur / I don’t see this as an issue which will ever totally be resolved.

+1

 

[GRAHASP]

I have the same issue with 3rd to 2nd downshifts. Very distinct clunk, and pretty consistent. May a little more pronounced when the shift happens while braking, versus coasting to a stop. It’s almost as though the control system is giving giving the throttle a slight blip at the same time that 2nd engages. I had the car at the dealer for service and raised this issue with them. The tech took it for a drive and said that it is not normal. He also took one of their demonstrators for a drive to compare. After the service, they said they couldn’t see anything obviously amiss, and would ‘open a ticket’ with Ineos. That was just before thanksgiving, so a month ago, but no feedback as yet. Interestingly if I shift into manual mode and do the 3rd to 2nd shift manually, it’s smooth as silk! All a bit worrying.

 

[Sonoranrover]

I have the same issue with 3rd to 2nd downshifts. Very distinct clunk, and pretty consistent. May a little more pronounced when the shift happens while braking, versus coasting to a stop. It’s almost as though the control system is giving giving the throttle a slight blip at the same time that 2nd engages. I had the car at the dealer for service and raised this issue with them. The tech took it for a drive and said that it is not normal. He also took one of their demonstrators for a drive to compare. After the service, they said they couldn’t see anything obviously amiss, and would ‘open a ticket’ with Ineos. That was just before thanksgiving, so a month ago, but no feedback as yet. Interestingly if I shift into manual mode and do the 3rd to 2nd shift manually, it’s smooth as silk! All a bit worrying.

If you go to manual at 3rd.
At 15miles/hour downshift to 2nd. Feels normal.
When mine is cold in morning no cluck.
If you brake harder as it downshifts in automatic no clunk.
Service manager has witnessed, agrees and is waiting for answer too.
Not getting worse at this time.

 

[255/85]

Sometimes with robustness you have to sacrifice a little bit of refinement but you’d think nowadays that should be easier to achieve. The whole clunk issue reminds me of driving old Land Rovers with spline wear on transfer case input shafts and the like, you sort of end up driving around the issue to keep things as quiet as possible. It’ll be interesting to watch and see if IA recommends any software or hardware changes to address the issue but I really don’t see that happening in a broad sense but more on a per-customer basis based on complaints.

Yeah, it has reminded me of drivetrain slack as well but I'm not certain now. We juat did a couple of thousand miles on road and it only happened two or three times. I'm now thinking brief torque converter lockup. I dunno really.

 

[c00kedg00se]

I too am experiencing a clunk while slowing down or slightly applying the brakes at speeds less than 40 miles an hour. I feel it under the pedals and I have an appointment with the service department on December 17 to investigate. It is fairly easy to replicate by accelerating or driving at normal street speeds and then lightly applying, feathering the brakes.

Just to give everyone an update, I was able to replicate the issue with the technician and he said it wasn’t normal. After analyzing with Ineos, they are certain it is in the front left control arm. For some reason the first recommendation is to replace the bolts (, which doesn’t make a lot of sense to me, new bushings would have made more sense. maybe a larger diameter?

I’ll let you know when they get installed, they are currently backordered. It’s never seemed like a transmission issue to me, it always felt like suspension, especially feeling the knock underneath the pedals.

 

[Clark Kent]

Just to give everyone an update, I was able to replicate the issue with the technician and he said it wasn’t normal. After analyzing with Ineos, they are certain it is in the front left control arm. For some reason the first recommendation is to replace the bolts (, which doesn’t make a lot of sense to me, new bushings would have made more sense. maybe a larger diameter?

I’ll let you know when they get installed, they are currently backordered. It’s never seemed like a transmission issue to me, it always felt like suspension, especially feeling the knock underneath the pedals.

This might be completely unrelated, but last June my agent did a service campaign to do a torque check on the control arm bolts. I have no idea what the note about the rear axle bearings noisy is. It's not something I reported.

 

[255/85]

Owl vans lost some control arm bolts. They mention it in their "safety wire" video.

 

[C-Mack]

Curious if anyone recently has found a fix for the 3 to 2 downshift clunk when slowing down for an intersection or traffic light? It happens only occasionally when I’m off throttle and gently on the brakes while slowing down. The clunk occurs just before coming to a complete stop as the transmission downshifts.

It got better after a few hundred miles after vehicle delivery but more recently and especially with the driveline warmed up it happens now and then. It’s never severe just a light clunk but you can feel and hear it in the driveline.

Has anyone had their vehicle software updated recently or more specifically their transmission software or adaptions reset and did it fix the problem? Furthermore, has any dealer officially confirmed the issue as either being mechanical or software related?

Is this still an issue on 2025 or 2026 models?

 

[Tenac]

Curious if anyone recently has found a fix for the 3 to 2 downshift clunk when slowing down for an intersection or traffic light? It happens only occasionally when I’m off throttle and gently on the brakes while slowing down. The clunk occurs just before coming to a complete stop as the transmission downshifts.

It got better after a few hundred miles after vehicle delivery but more recently and especially with the driveline warmed up it happens now and then. It’s never severe just a light clunk but you can feel and hear it in the driveline.

Has anyone had their vehicle software updated recently or more specifically their transmission software or adaptions reset and did it fix the problem? Furthermore, has any dealer officially confirmed the issue as either being mechanical or software related?

Is this still an issue on 2025 or 2026 models?

Word is a software update coming for the transmission. dunno how true or when but sounds legit.

 

[C-Mack]

Nothing more confidence inspiring when in relates to software updates and IA. Hopefully the update rumor is indeed legit but knowing IA, it’s somewhere between another 6 to 12 months and never away. Probably not something we should collectively hold our breath for I would say.

At this rate stacking up all the warranty or service jobs so I have to only make one trip to the dealer they are likely never going to see my vehicle again. Fortunately, I’m handy with the spanners for all the basic maintenance in the mean time… fingers crossed!

 

[Cheshire cat]

I have experienced a clunk when braking quite hard to make a right turn. Only happened four or five times over three years. Not worrying, but would still like to know what causes it.