Jeep Garage  - Jeep Forum

Jeep Garage - Jeep Forum (http://www.jeepgarage.org/forums.php)
-   Trouble Shooting/Problems/Service (http://www.jeepgarage.org/f107/)
-   -   Rear bump feel when accelerating (http://www.jeepgarage.org/f107/rear-bump-feel-when-accelerating-42770.html)

ajs800 05-31-2012 08:10 AM

Rear bump feel when accelerating
 
I don't know how to really describe it except that many times after coming to a stop (like at a stop light) and then accelerate, sometimes i feel a bump in the rear. Almost as if there is something loose...it's kind of like a disconnect feeling. I don't feel it any other time except after coming to a stop and then accelerating. Anyone else experience this issue?

JRNYC 05-31-2012 08:20 AM

Re: Rear bump feel when accelerating
 
Ahh the bowling ball in the trunk syndrome.. Yes this is your rear shock(s)/suspension. It is a known issue for the Quadralift system. There is a TSB or whatever they call it against it. I had my rear right shock replaced from day one because of a loud creaking noise... they said faulty shock bushing and replaced the shock..

Now I have exactly what you have after a few months.. and it has snowballed into the front end which now gives a clicking feel in the steering wheel. ntw a tsb against that also.

This is a big issue. You might have a inconvenient road ahead of you getting it fixed/replaced numerous times. Hopefully not. Start looking into the Lemon Law. Chrysler has a special group taking care of these issues with our vehicle now. Apparently they are buying back the more problematic units. But it will take a few trips and failures to get that.

This will be my 2nd trip for the suspension. I dont doubt I will be going back 2 or 3 more times.

JTS97Z28 05-31-2012 08:46 AM

Re: Rear bump feel when accelerating
 
I have a feeling it's not a suspension issue he is speaking of. He might be talking about the drivetrain thug when starting from a stop. It basically feels like a quick jolt as you first start accelerating. It's common and apparently is the transfer case engaging 4wd or whatever. Doesn't necessarily feel normal, but from what they say it is normal. My new 2012 does it on occasion and its always from a stop you described.

ajs800 05-31-2012 08:46 AM

Re: Rear bump feel when accelerating
 
really? It is very subtle and there has been no creaking or any other strange sounds or feelings once it is moving. Honestly, I don't think the majority would even notice it. I have a few things that need to be looked at the next time it goes to dealer so I'll add this to the list.

What year do you have and how many miles?

ajs800 05-31-2012 08:48 AM

Re: Rear bump feel when accelerating
 
Quote:

Originally Posted by JTS97Z28 (Post 636921)
I have a feeling it's not a suspension issue he is speaking of. He might be talking about the drivetrain thug when starting from a stop. It basically feels like a quick jolt as you first start accelerating. It's common and apparently is the transfer case engaging 4wd or whatever. Doesn't necessarily feel normal, but from what they say it is normal. My new 2012 does it on occasion and always from a stop.


exactly! I would say it is what you're describing versus a suspension issue. It doesn't always do it and it does feel more drivetrain related.

Raptor 05-31-2012 09:59 AM

Re: Rear bump feel when accelerating
 
Quote:

Originally Posted by JTS97Z28 (Post 636921)
I have a feeling it's not a suspension issue he is speaking of. He might be talking about the drivetrain thug when starting from a stop. It basically feels like a quick jolt as you first start accelerating. It's common and apparently is the transfer case engaging 4wd or whatever. Doesn't necessarily feel normal, but from what they say it is normal. My new 2012 does it on occasion and its always from a stop you described.

Yes I also experience a drivetrain bump intermitantly and only when accelerating from a complete stop. Doesn't do it every time, and when I try to make it happen from a stop I don't seem to be able to replicate it! Mine is a 2012 Overland Summit w/the 5.7L engine.

JRNYC 05-31-2012 10:17 AM

Re: Rear bump feel when accelerating
 
Ok so maybe drivetrain instead of suspension.

One thread in here was specifically for that issue and the fix was to replace some suspension components. The thread even posted the tsb for with that info. I will try and find it.

However a thud to me is not normal. Its juts a bigger problem waiting to happen imo. I didnt spend XX,XXX on a jeep to have a thud.

Just my view.

JRNYC 05-31-2012 10:24 AM

Re: Rear bump feel when accelerating
 
This isnt the tsb I was talking about but here is a tsb specifically referring to a squeak/clunk from the rear suspension.

9/11 but the suspension can in fact give you the thud. remeber its not a niormal suspension on QL.

USA1fan 05-31-2012 05:12 PM

Re: Rear bump feel when accelerating
 
Could it be driveline lash? My 2004 Silverado had similar symptoms as described here, but it was just the driveline (shaft to rear diff, mainly) unloading as I came to a stop (leaving just a little slack), and then when the throttle was applied, causing the slack to be taken up- [clunk]. I was told it was normal during the next regular service, and it never caused any problems.

ajs800 05-31-2012 09:19 PM

Re: Rear bump feel when accelerating
 
Quote:

Originally Posted by JRNYC (Post 636966)
This isnt the tsb I was talking about but here is a tsb specifically referring to a squeak/clunk from the rear suspension.

9/11 but the suspension can in fact give you the thud. remeber its not a niormal suspension on QL.


It's definitely not suspension related.

savvas 05-31-2012 09:20 PM

Re: Rear bump feel when accelerating
 
This is common in a lot of 4WD vehicles, and it is often the movement of a drive shaft sleeve that might be dry. If you top up the grease in the sleeve and it goes away, then that is it.

I had this in the Australian equivalent of an Isuzu Trooper. A permanent fix was to find an old engine valve spring that would fit into the sleeve, and then re-install the drive shaft. The compression of the spring keeps the fit of the drive shaft nice and tight and the thump went away and never came back. I did around 150000kms with the spring in place.

I dont know if the WK2 has a sliding drive shaft sleeve or not, but if it does then it's worth looking at this as a starting point.

JRNYC 06-01-2012 10:24 AM

Re: Rear bump feel when accelerating
 
Quote:

Originally Posted by ajs800 (Post 637261)
It's definitely not suspension related.

Just interested in finding out how you eliminated the suspension as being the cause?


All times are GMT -5. The time now is 01:09 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community