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-   -   2011 vs. 2012 shudder (http://www.jeepgarage.org/f107/2011-vs-2012-shudder-33266.html)

andylcg 12-30-2011 10:07 AM

2011 vs. 2012 shudder
 
I was wondering if Jeep fixed the Shudder problem between 15-20mph on the 2012 Jeep GC's?

Sliter'12Overland 12-31-2011 06:57 AM

Re: 2011 vs. 2012 shudder
 
Quote:

Originally Posted by andylcg (Post 542625)
I was wondering if Jeep fixed the Shudder problem between 15-20mph on the 2012 Jeep GC's?

I find the '12 to be enjoyable on the road in auto or sport with the shifter in D on all in town short trips it is only on the highway around 60-80MPH holding steady throttle that the shudder comes in waves.

ColdCase 12-31-2011 09:11 AM

Re: 2011 vs. 2012 shudder
 
My late 2011 build has no shudder.

Sliter'12Overland 12-31-2011 02:27 PM

Re: 2011 vs. 2012 shudder
 
Quote:

Originally Posted by ColdCase (Post 543231)
My late 2011 build has no shudder.

Do you have the ORAII package? I have a feeling it is the QD and MDS I am also running 265 65 R18 Blizzaks so for all I know it could be the tires. They are very soft tires I can seperate the sipes with my fingers I plan to get a set of the factory 20's with some good all-season tires for the summer months and next set of snows will be Silent Armors the Blizzaks are overkill with this all wheel drive system.

jgc4ever 12-31-2011 04:35 PM

Re: 2011 vs. 2012 shudder
 
I have a 2012 Overland 4x4 Hemi with 2900 miles. I don't have a shudder. I have 20" wheels and QTII (no QDII/ELSD)

ColdCase 12-31-2011 05:05 PM

Re: 2011 vs. 2012 shudder
 
No ORA but its a V8 overland with QD. I run both 18 inch blizzaks on OEM wheels and 20 inch OEM goodyears, no observed shudder regardless. There are times when the blizzaks are a bit rough on right turns, but most of the time they are smooth running. They are optimized for icy conditions, soft otherwise. The 20s seem to be always smooth. I have close to 14000 miles total.

The MDS rumble is noticeable, more so in normal mode than sport mode where it seems to kick out more quickly and at a higher RPM.

Sliter'12Overland 12-31-2011 06:05 PM

Re: 2011 vs. 2012 shudder
 
I took a 50 mile drive this morning mixed highway and side road driving with some ice on the side roads. This thing is a beast on ice the QD and Blizzaks are awesome and the fact that we're talkin 5000+ lbs. It will walk up sheer ice at a pretty decent incline. Further on the shudder I am confident that it has something to do with the new "6" speed shift mapping and the mds this new ratio and the cylinder deactivation needs fine tuning. If I put the ERS into 5 and drive normally it is perfect there is no shudder it is even more responsive and smooth in tow/haul, however mileage gets no help this way.

jp467 12-31-2011 06:21 PM

Re: 2011 vs. 2012 shudder
 
Is this really a shudder or is it a vibration? I just ask because it seems on these jeeps the word shudder has been used it describe almost every issue. It would not suprise me if chrysler came out with a software update for the new 6 speed program. This seems to be the history, I really don't understand why they can't seem to get these things programmed before they hit the market.

ColdCase 12-31-2011 08:18 PM

Re: 2011 vs. 2012 shudder
 
Quote:

Originally Posted by Sliter'12Overland (Post 543438)
I am confident that it has something to do with the new "6" speed shift mapping and the mds this new ratio and the cylinder deactivation needs fine tuning. If I put the ERS into 5 and drive normally it is perfect there is no shudder it is even more responsive and smooth in tow/haul, however mileage gets no help this way.

You do know there is no new ratio in the 6 speed, the ratios and gearing are the same in these transmission as the so called multi-speed in the 2011 as well as for years in Jeeps and other chrysler vehicles. Shift programing has changed over time. The torque converter was changed for 2012 in an attempt to better mpg with minimum harshness. Perhaps you are feeling the torque converter clutch engaging and disengaging as it flutters. This and the MDS would be most noticeable in 6th when the rpms are low. When you drive in tow haul or shift to ERS 5, the vehicle does not use the second overdrive (6th) where the flutter would be most noticeable. MDS is disabled in 5 (and ERS 6), so that eliminates that vibration (not sure if MDS gets disabled in tow/haul). Tow haul also adjust shift points to a higher rpm where smooth operation is easier to obtain.

So the jeep gives you a real choice between a smooth responsive vehicle and one that squeezes the last mile out of that gallon, with some harshness. There shouldn't be much harshness, however.

You may feel and hear some vibration when MDS is engaged and sometimes when driving in second overdrive due to the torque converter flutter, thats just the way it is.. normal for these vehicles.


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