Clunk when changing direction at low speed

[SmartDrug]

I've been chasing this sound for a few weeks now, it's a thunk/clunk sound coming from around the transfer case to the rear of the HMMWV. It happens when I'm making a 90 +/- degree turn , left or right, at neighborhood speeds, for example when pulling into my driveway. I've checked all the ball joints, the steering linkages, Pitman/idler arm, driveshaft U-joints, wheel lug torque, etc. basically anything that moves and can't find any slop/play, as a result, I cannot repeat it nor trace it. It is a low mileage/use M1123 converted to a 4 man, any thoughts on where to look next, I'm all ears.

Thank you

 

[MarkM]

Check the tranny mount.

Mark

 

[Mogman]

I've been chasing this sound for a few weeks now, it's a thunk/clunk sound coming from around the transfer case to the rear of the HMMWV. It happens when I'm making a 90 +/- degree turn , left or right, at neighborhood speeds, for example when pulling into my driveway. I've checked all the ball joints, the steering linkages, Pitman/idler arm, driveshaft U-joints, wheel lug torque, etc. basically anything that moves and can't find any slop/play, as a result, I cannot repeat it nor trace it. It is a low mileage/use M1123 converted to a 4 man, any thoughts on where to look next, I'm all ears.

Thank you

Probably the Torsen limited slip diffs, normal to pop and snap at low speeds while turning.

 

[TOBASH]

What gear is your transfer case in?

make sure it is H and not HL

 

[MarkM]

What gear is your transfer case in?

make sure it is H and not HL

Good point!

 

[TOBASH]

Good point!

My neighbor just had this issue… I took one look and … He was in HL.

 

[Retiredwarhorses]

Sounds like possibly rear brake chatter at low speeds.

 

[osteo16]

Sounds like possibly rear brake chatter at low speeds.

Sounds like a HMMWV

 

[papakb]

I had one of my brake calipers come lose and it would clunk when I was stopping. Since he didn't say what vehicle he was running I wonder if this could be the old driveline Ebrake banging? It's near enough to the Tcase. And yes, there are still a number of those old doggies out there running around!

 

[SmartDrug]

Took a few days of poking around and I found the source of the sound, turns out I was way off as far as location. The sound is coming from the brakes, there is an almost imperceptible amount of wobble in the carrier, but it makes a pronounced clunk when wobbled by hand. All the bolts are secure, so I'm guessing it's just the nature of the beast, but will be doing some inspecting and testing this afternoon.

Thank you all for the advice!

 

[papakb]

Check the brake caliper mount to the diff to make sure it's tight. Mine felt good until I put some umph into it and then it moved.

 

[SmartDrug]

Sorry to bring up this old thread, but I finally got to the bottom of this one. Checked everything several times, tried various things, replaced a handful of components, the thud kept coming back.

Finally, this afternoon, while mowing the lawn, I’m looking at the HMMWV and it dawns on me, maybe the front and rear shackles are swinging around and bumping into their brackets and that’s what I’m hearing/feeling. So I grab a handful of zip ties, secured them and went for a 20 minute drive- sure enough, clanking is gone.

I feel very silly about this one, but maybe someone will learn from my stupidity here. Cheers!