After doing some research on the causes of shudder, I discovered that old and dirty gear oil in the rear differential can cause shudder. I just changed the gear oil and the shudder is gone.

So my shudder was not due to the TC but to the dirty gear oil in the differential.

The oil in the differential hadn't been changed since it came out of the factory. My fault for not checking earlier, I bought the jeep with 37,000 miles on it in 2011 it now has 65,000 miles, it was due for a change. I'll do the front tomorrow.

So if any of you are experiencing continued shudder even after you replaced your Torque converter, before you tare into your transmission again, change the rear differential oil with 70 OZ of 75 - 90 synthetic gear oil.

The worst part of the job was getting the old gasket off.

Here is a good write up on how to do it: http://www.jeepkj.com/forum/f202/how-ch ... ils-28670/

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2006 Liberty Limited CRD, Deep Beryl Green, Yeti tune, Arp studs, new cams, rockers, lifters, TB. "Green Monster"
2005 Liberty Sport CRD, Deep Beryl Green, GDE Hot Tune, ARP studs. "Rocket"
1982 Fiat 124 Spider Convertible. "Fiona"

Glad you found it. Guys who mess around with diffs here say the rear limited slip gets dirty faster than the front.

Neither are new technology. Dana 30 and Chrysler 8 1/4 limited slip have been around a while. Doesn't your Sahara have the 8 1/4?

FWIW, I use Dino front and rear.. . 80/90 since I don't tow.

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'05 Sport CRD 107k miles. NOBODY knows everything.

TJ2, I change the rear end oil in the TJ on schedule not sure what it is.

The gear oil in the CRD was sludgy .... black oily thick stuck on cake at the bottom, it took a while to get it out. It was pretty bad, I'll never let that happen again. I plan to change the gear oil at 12,000 miles intervals.

Too bad the rear end doesn't have a drain plug, it would make the task a cinch.

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2006 Liberty Limited CRD, Deep Beryl Green, Yeti tune, Arp studs, new cams, rockers, lifters, TB. "Green Monster"
2005 Liberty Sport CRD, Deep Beryl Green, GDE Hot Tune, ARP studs. "Rocket"
1982 Fiat 124 Spider Convertible. "Fiona"

Did mine a while back and used a "reusable gasket" from lubelocker instead of the RTV. Also took some brake cleaner to it to get it nice and clean. The diff oil just looked blackesh and had a rotten egg smell to it.

viewtopic.php?f=23&t=55217

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Horse Power: How fast you hit a wall.
Torque: How much of the wall you take with you.

06 CRD
OME HD w/clevis top plate
JBA 4.5 UCAs
245/75/16r Goodyear Duratrax
Fumoto Valve, V6 ABM
Rock Lizard Super Skinks
Cobra 75 WX ST
ECO GDE tune, 2.5 straight piped
ProVent, Samcoed
Non F37ed TCM
DieHard P1

Do you have the TracLok, clutch type LSD diff? If you want it to last as long as possible, I suggest SWEPCO 212. This an 85-140, multigrade, NON-SYNTHETIC, gear oil with MOLY. Also, it does NOT require the addition of a friction modifier for the aforementioned type of LSD.

If you have an open diff, I cannot understand how a gear oil change could influence "shudder" in any way.

(BTW, when clutch type diffs do not operate smoothly, it is referred to as "chatter"?)

DOC

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2005 KJ CRD Ltd Detroit TrueTrac Bilsteins G2 GDE "HOT" ECU GDE TCM "Tow Tune" "euro" TC SEGR Weeks Elbow New HG at 130K ARPs Clean CAT aFe Filter Magnaflow Exhaust EHM Cumminos In-Tank Lift Pump Hayden Fan Clutch Nylon Fan VH Enabled with GDE lower shutoff point Recalibrated Temp Gauge Tekonsha Prodigy Sears P-1 ZDDP

I do not know..... checking with jeep.



Me either, but according to some of the experts around town, it does happen.

One of the techs said the following/l " those gears need to slide smoothly at high speeds. If the there is a hint of hesitation due to poor gear oil lubrication, then shudder can occur."

We need a lubrication engineer to explain what happens here.

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2006 Liberty Limited CRD, Deep Beryl Green, Yeti tune, Arp studs, new cams, rockers, lifters, TB. "Green Monster"
2005 Liberty Sport CRD, Deep Beryl Green, GDE Hot Tune, ARP studs. "Rocket"
1982 Fiat 124 Spider Convertible. "Fiona"

A 2005 CRD should have a clutch type rear diff.
A 2006 should have a open diff.

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U.S. Army Retired

Mine's a 2005 and limited slip was an option (that I do NOT have). Been using full syn since day one and changing every other oil change (since that's what the service interval is, even though it seems a bit looney). I may switch to dino on the next one to try it out. Never had any issues except for the rear bearing replacement that a driveline shop said they were SURE was going bad (which ended up being a bad front brake caliper...not going back there again).

I think the only way you would have something in the diff being the cause for "shudder" is if it's slipping under power when you DO have traction and there's a slight torque surge from the gear change.

Dan

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2005 Silver CRD Limited
245/75R16 GoodYear Duratracs
Fumoto drain | ProVent CCV Filter
Stanadyne FM100 filter | Cummins fuel pump
GDE Eco | SEGR | BoulderBars | FrankenLift | Frankenskids

FYI...don't forget to change the front end and transfer case oil also. I change all of mine every 30k.

Sorry but I still get a shudder at times.

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05 Liberty CRD Sport with Leather 115k
GDE ECO, No EGR, no FCV, (system gone)
Oil Drain plug P/N 090-039
K&N Air Filter, 2nd gen Fuel filter head
NEW Rockers & lifters
Mobil 1 0w-40
Stant 13519 195 deg inline Thermostat.
0 281 002 845 MAP
Etecno GX3123 7v Glow Plugs
Advance Gold 800CCA Battery
Traded it for a Quality VW TDI