Loud Clunk from driveline

[Merlins Jeep]

Have a possible issue with a new JLU (2025) with 35 package 2.0T.

Have 600 miles on the jeep and took it out to get its feet dirty on a simple trail. Was is 4H, made a slow hard left and heard a loud clank (only way I can describe it), that soundled like something, bound up, broke from the front right tire area and the Jeep came to a stop.

After a second of shock then lookaing over the controls, the transfer case was in neutral and when i shifted back into 4H, it was able to be driven again.

it appears to be driving as before but then again I do not have much of any time in jeeps and to me, feels like its drifting around more then when I purchased at freeway speed but ?. I do also hear a strange whistle or pump sound from the power steering that continues when moving the wheel and then for a few seconds after the wheel stoped turning. Not sure if that is related and dont recall hearing it when i first got the Jeep.

I know this is a good community with a ton of experience, does anyone have advise on the above? Any help would be appreciated.

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[HiJinx69]

On what surface were you on? If the surface was somewhat hard, it might have been the wheel hopping (i think that's the right term).

 

[Merlins Jeep]

Good thought HiJinx69 but it was on slippery mud.

 

[Heimkehr]

My first guess is driveline binding due to insufficient per-tire slip on the front axle when in 4H. That the sound occurred during a "hard left", after which the transfer case self-selected Neutral, only reinforces this suggestion.

Perhaps the mud wasn't as slippery as perceived, with the full weight of the vehicle on it.

Anyway...monitor things to ensure continued smooth operation.

As for the Jeep moving around in its lane at highway speeds: the cold tire pressure recommendation is usually 37 PSI. Reset to that figure, if necessary, and retest.

 

[Merlins Jeep]

Thanks Heimkehr so the transfer case dumps into N when there is a problem? never had a 4X that bound up before both IFS and solid front axle - the lockers were not on so isn't the Dif a limited slip in my case?

The noise was frightening when it gave way....

 

[Bob Burd]

I've had mine pop out of gear occasionally. I chocked it up to not having fully engaged it to start.

 

[Merlins Jeep]

Did your jeep make any clunking noise when it jumped out of 4H Bob Burd ? Funny enough, I originally thought my knee knocked the transfer case to N.

 

[blackJLURubi]

Sounds like transfer case wasn’t fully engaged and it popped out of 4H. This can be common on a new rig that hasn’t been in 4Hi much

 

[Heimkehr]

Thanks Heimkehr so the transfer case dumps into N when there is a problem?

When fully/correctly engaged, the transfer case shouldn't then disengage from the current selection, absent the driver moving the lever.

Sometimes, though, full engagement on a new Jeep -- particularly 4 Low -- can occasionally be tricky to maintain.

 

[roaniecowpony]

When fully/correctly engaged, the transfer case shouldn't then disengage from the current selection, absent the driver moving the lever.

Sometimes, though, full engagement on a new Jeep -- particularly 4 Low -- can occasionally be tricky to maintain.

When transfer case shifters had rods instead of cables they were much more positive.

 

[Beach Nut]

Have a possible issue with a new JLU (2025) with 35 package 2.0T.

Have 600 miles on the jeep and took it out to get its feet dirty on a simple trail. Was is 4H, made a slow hard left and heard a loud clank (only way I can describe it), that soundled like something, bound up, broke from the front right tire area and the Jeep came to a stop.

After a second of shock then lookaing over the controls, the transfer case was in neutral and when i shifted back into 4H, it was able to be driven again.

it appears to be driving as before but then again I do not have much of any time in jeeps and to me, feels like its drifting around more then when I purchased at freeway speed but ?. I do also hear a strange whistle or pump sound from the power steering that continues when moving the wheel and then for a few seconds after the wheel stoped turning. Not sure if that is related and dont recall hearing it when i first got the Jeep.

I know this is a good community with a ton of experience, does anyone have advise on the above? Any help would be appreciated.

 

[Beach Nut]

It’s new…take it to the dealership, document everything and take it from there.

 

[Bob Burd]

Did your jeep make any clunking noise when it jumped out of 4H Bob Burd ? Funny enough, I originally thought my knee knocked the transfer case to N.

Yes.
And it's possible to accidentally knock it to neutral, but I think more likely just not fully engaged.

 

[TransientMole]

Have a possible issue with a new JLU (2025) with 35 package 2.0T.

Have 600 miles on the jeep and took it out to get its feet dirty on a simple trail. Was is 4H, made a slow hard left and heard a loud clank (only way I can describe it), that soundled like something, bound up, broke from the front right tire area and the Jeep came to a stop.

After a second of shock then lookaing over the controls, the transfer case was in neutral and when i shifted back into 4H, it was able to be driven again.

it appears to be driving as before but then again I do not have much of any time in jeeps and to me, feels like its drifting around more then when I purchased at freeway speed but ?. I do also hear a strange whistle or pump sound from the power steering that continues when moving the wheel and then for a few seconds after the wheel stoped turning. Not sure if that is related and dont recall hearing it when i first got the Jeep.

I know this is a good community with a ton of experience, does anyone have advise on the above? Any help would be appreciated.

I am very intrigued - I also have a 2025 JLU. At around 700 miles I was working to get the transfer case into Neutral so we could flat tow it (We had done this same thing several times before). Transmission was in N, and I went from 2H to N - seemed to go OK. However while the transfer case shifter on dash indicated we were in "N", it was actually still engaged (4H from what I could tell). I figured it was just a fluke where something wasn't pushed all the way, so I shifted down into 4L which resulted in a pretty loud engaging clunk which made me go "oof"... I was then able to go back into N and everything seemed OK, but I have been hyper sensitive to it since making sure all is OK since this is our first Jeep. Other than this, we really haven't "used" 4H or 4L.

Since then, I have noticed a couple things - And maybe they are completely unrelated, but I found it odd how similar it was to what you were seeing :

1) When first starting, and shifting into R (2H) it seems to make a brief clunk that I never noticed before (but again, I'm not really sure what normal is).

2) I also noticed a type of "whistling harmonic" that occurs randomly at low speeds (like 10mph) and at the end of a turn while straightening out (only ever happens during a turn when it does). It only lasts about a second and I cant reliably recreate it on demand. The sound is less of a whistle, and sounds more like the sound you would get out of a Reed instrument or one note harmonica, or wind coming through an old window. My first thought was something like a vacuum line leak, but I haven't had a chance to troubleshoot it - and when I saw your post I wondered if it might be similar.

I thought it was curious - interested to see if anyone else has some good input - following!

 

[roaniecowpony]

I am very intrigued - I also have a 2025 JLU. At around 700 miles I was working to get the transfer case into Neutral so we could flat tow it (We had done this same thing several times before). Transmission was in N, and I went from 2H to N - seemed to go OK. However while the transfer case shifter on dash indicated we were in "N", it was actually still engaged (4H from what I could tell). I figured it was just a fluke where something wasn't pushed all the way, so I shifted down into 4L which resulted in a pretty loud engaging clunk which made me go "oof"... I was then able to go back into N and everything seemed OK, but I have been hyper sensitive to it since making sure all is OK since this is our first Jeep. Other than this, we really haven't "used" 4H or 4L.

Since then, I have noticed a couple things - And maybe they are completely unrelated, but I found it odd how similar it was to what you were seeing :

1) When first starting, and shifting into R (2H) it seems to make a brief clunk that I never noticed before (but again, I'm not really sure what normal is).

2) I also noticed a type of "whistling harmonic" that occurs randomly at low speeds (like 10mph) and at the end of a turn while straightening out (only ever happens during a turn when it does). It only lasts about a second and I cant reliably recreate it on demand. The sound is less of a whistle, and sounds more like the sound you would get out of a Reed instrument or one note harmonica, or wind coming through an old window. My first thought was something like a vacuum line leak, but I haven't had a chance to troubleshoot it - and when I saw your post I wondered if it might be similar.

I thought it was curious - interested to see if anyone else has some good input - following!

As I stated earlier, the cable shifter systems are not as postive as the old rod shifters.

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