I don't get to drive the Jeep much. I drove it over the weekend, and except for one alarming incident, it drives smoothly and quietly.

I accelerated from a stop to get ahead of the car next to me, to merge onto the highway. I hit it hard, and as I drove over a section of rippled pavement there was a horrendous noise from the rear, sort of like a complete freewheeling, then a clash or clang as it caught. And then it was quiet and strong again, and accelerating normally.

It's quiet during turns, and it accelerates smoothly and strong on smooth surfaces. I actually haven't been underneath it yet, but I though I'd just put the tranny in neutral and apply the parking brake, then try to rotate the drive shaft by hand to check the slop. Does it sound like I'm on the right track?

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'05 Liberty CRD B100, SEGR - SOLD

'01 Beetle TDi B100, EGR delete
'83 Mercedes 240D B100, no EGR

--- SEGR Builder ---

My parking break doesn't work after my first brake job. Don't get killed.

As to the shaft, I bent mine shifting the TC while trying to pull a friend off of ice with a strap. The whole Jeep would shake for everything. Even on blacktop without throttle. I really noticed is when I coasted to stops.

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2005 Black KJ Sport CRD,
GDE Full Torque ECO TUNE, GDE Transmission ECO Tune,
Samco British Racing Green Hoses
Build Date 1/05
200k miles.
Original Owner

The driveshaft seems fine. The u-joints are both tight. I do have shaft movement of approximately 1/8" at the transfer case flange, presumably differential gear lash. Maybe the diff needs a looking at? Or is this something more likely to be a transfer case issue?

I did have the fluids all changed last year, whatever the 60k service is, but I think this issue has been present all the while. First time I got it stuck in the snow, I did some spinning and rocking to get out, and this horrible noise happened then too.

Any input is welcome.

_________________
'05 Liberty CRD B100, SEGR - SOLD

'01 Beetle TDi B100, EGR delete
'83 Mercedes 240D B100, no EGR

--- SEGR Builder ---

Has no one heard this? Any speculation?

_________________
'05 Liberty CRD B100, SEGR - SOLD

'01 Beetle TDi B100, EGR delete
'83 Mercedes 240D B100, no EGR

--- SEGR Builder ---

I'm guessing here, but maybe your transfer case chain is loose and skipping teeth. I can't see the rear diff gears skipping teeth without grenading. And if they were out of adjustment they would make noise all the time. Seems like it must be coming from the t-case.

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05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.

Can you be more specific about the shaft movement?
Is the movement you measured rotational? Or are you able to slide the shaft in and out the the t-case?

It should not be able to slide in and out. If it does, the rear pinion bearings are bad.

Some rotational movement is normal due backlash between ring and pinion gears.

Could it be that you t-case somehow briefly popped into neutral while on that rough patch?

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U.S. Army Retired

Shaft movement is purely rotational, and seems appropriate for rear end gear lash, and normal acceleration is smooth, even through turns. I couldn't get the drive shaft to move out of the transfer case, but it's possible under suspension extension there may be an issue with the yoke....I had not considered that until now.

The noise seemed like it was in the rear, so I haven't really considered the transfer case being an issue.

_________________
'05 Liberty CRD B100, SEGR - SOLD

'01 Beetle TDi B100, EGR delete
'83 Mercedes 240D B100, no EGR

--- SEGR Builder ---

Even under full suspension extension, the drive shaft should never loose engagement with the
splines on the t-case ouput. If it did, the shaft would be lying on the ground.

Another possibility is the locking or limited-slip differential.
I dont know much about the 'lockers" in our Jeeps, but I have experienced on another
vehicle where the splines or locking teeth briefly fall out of alignment. Then it acts as if its
in neutral. Then suddenly it slams back into place and everything is normal again.

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U.S. Army Retired