Normal JL Clunking?

[CFC4953]

Hey guys. I have a brand new 2021 JLUR, Under 1,000 miles and already put on the AEV 2.5 Lift with 37 Nittos. I told the service rep at Jeep to check out a clunking noise that I hear in low gears and low speeds. Usually in parking lots or doing soft stops at a stop sign. It seems like the sweet spot is 7-8 mph and there is a soft clunk which seems to be in the rear somewhere. I don't feel it I only hear it. Does anyone else experience minor soft clunks at low speeds. It seems like there is some play somewhere when accelerating. This only happens when I tap the gas very lightly at low speeds. The tech at Jeep said it's very normal but I don't believe anything Jeep service techs say. Would love to hear some feedback as it's driving me crazy

Sponsored

 

[ajridgedell]

Well mine does that, sometimes I hear it just idling too. I have been curiouse about it, but I'll assume its normal since yours does it too and I don't see anything else wrong with mine. 2021 JLR 2.0.

 

[Canuck714]

If you do a search for clunking noise LSD you will find a hornets nest of the same issue. Apparently there is an issues with the rear diff since 2018. Some people have had all the bearing, ring/pinion replaced only to have the issue come back due to loose tolerances in the LSD carrier.
My wifes just started doing it as well.
So far there is not a solid "fix" for it

 

[Dgr401]

Check the jack. The jack is held in place with a little up tension. The tension on mine had backed off just enough to let the jack move around a little. It is worth checking..

 

[lepcat]

Check your front tie rod end links. Mine were loose from the get go.

 

[jessedacri]

If you do a search for clunking noise LSD you will find a hornets nest of the same issue. Apparently there is an issues with the rear diff since 2018. Some people have had all the bearing, ring/pinion replaced only to have the issue come back due to loose tolerances in the LSD carrier.
My wifes just started doing it as well.
So far there is not a solid "fix" for it

OP has a Rubicon so this shouldn't be it. No LSD in the locker-equipped D44s.

 

[Canuck714]

OP has a Rubicon so this shouldn't be it. No LSD in the locker-equipped D44s.

Oooops.. missed the Rubi part!

 

[CFC4953]

OP has a Rubicon so this shouldn't be it. No LSD in the locker-equipped D44s.

Not the LSD, I don't think I have one since I have a Rubicon. From experience with my JK (which had the same issue, everyone said it was fine) it seems to be play in the driveshaft/rear. All other components are tight. If I had to self diagnose it I would say that this sound is always there but when you put 37s on it exaggerates it a bit. Like I said it only happens at low speeds when I tap the gas

 

[DavidArmen]

As you say, it’s very possible it’s in the driveline. I don’t hear that same clunk as you in the rear but the jeep always clunks when I put it in reverse especially if the jeep is cold. And also, my front diff always clunks when I take it in and out of 4H; I hear a nice clunk after I put it in 4H and accelerate a little, probably because of the FAD connecting and the front diff gears starting to spin, and I hear a lower clunk when I go back to 2H. I also hear the sound of the electric motor of the FAD as it engages and disengages but the clunk seems to be coming from the diff itself. I assume it’s normal.

 

[Mikester86]

If you have adjustable track bars, make certain the mechanism that locks them to their set length is tight and to torque spec. Ask me how I know, lol.

 

[CFC4953]

As you say, it’s very possible it’s in the driveline. I don’t hear that same clunk as you in the rear but the jeep always clunks when I put it in reverse especially if the jeep is cold. And also, my front diff always clunks when I take it in and out of 4H; I hear a nice clunk after I put it in 4H and accelerate a little, probably because of the FAD connecting and the front diff gears starting to spin, and I hear a lower clunk when I go back to 2H. I also hear the sound of the electric motor of the FAD as it engages and disengages but the clunk seems to be coming from the diff itself. I assume it’s normal.

I'm just curious as to what it is making the noise. If it's normal that's fine, the tech can't seem to accurately tell me what it is but says it's normal. I'll change the clunk to more like a pop, as a clunk on paper sounds worse than a pop. This could just be normal gear changing and it's hard for people to hear it if their not listening to it. I just have some leverage at the dealer if it's something major to fix with 1,000 miles on it vs 30,000 down the road

 

[CFC4953]

I'll also add that the sound is similar but not as loud as when you put your jeep in reverse when your on a hill. It seems to be a similar sound but much softer

 

[oldcjguy]

I'll also add that the sound is similar but not as loud as when you put your jeep in reverse when your on a hill. It seems to be a similar sound but much softer

It may be from the new suspension components. The clunk may be the normal play between accel and decel in the driveline. Did your lift include new control arms? Usually the bushings in after market control are stiffer and transmit more noise through the chassis.

$.02

 

[DavidArmen]

I'm just curious as to what it is making the noise. If it's normal that's fine, the tech can't seem to accurately tell me what it is but says it's normal. I'll change the clunk to more like a pop, as a clunk on paper sounds worse than a pop. This could just be normal gear changing and it's hard for people to hear it if their not listening to it. I just have some leverage at the dealer if it's something major to fix with 1,000 miles on it vs 30,000 down the road

I’m no expert at all but from what I know, the ring and pinion gears are designed to have play. Now I don’t know how much play they have but, at least when it comes to my front diff, I think if the amount of play is large enough, the sound may possibly be from the pinion gear starting to spin and one of its’ teeth making contact with one of the teeth on the ring gear and that fast contact is what makes the noise. This might be completely wrong but I can’t imagine what else it can be, especially with my front diff, since it only makes the noise once i put it into 4H and only after I accelerate. The noise isn’t there if go into 4H and I just depress the brake pedal and let the jeep roll. This also tells me that the noise may be gear contact since I only hear it if I accelerate, which causes the pinion gear to spin rapidly from a stop so the tooth contact with the ring gear has more force and so it makes a louder sound. But yeah this assumption might be totally wrong because I don’t know much about diffs.

 

[rocksarntpeople]

I experience something similar. Stock 2019 JLU Sahara with 37,000 miles. I have tried to get it looked at for about a year and half and no dealer can seem to answer what it is or what's causing it.

For what its worth though, for me it has progressively gotten louder and more violent and recently over the past 2 weeks, the "Service 4WD" light has been going on and off. Im not sure weather its related, but its going back in to the shop to get it checked again tomorrow so I will report back with any findings.

Sponsored