Last post on Sep 29, 2013 at 11:13 PM
You are in the Jeep Cherokee and Jeep Grand Cherokee
What is this discussion about?
Jeep Grand Cherokee, Jeep Grand Cherokee SRT-8, Jeep Commander SRT-8, SUV
#159 of 202 Re: Vibration with Hemi at 70-75 MPH [jaybee5]
Mar 20, 2008 (9:52 am)
I must say I appreciate my technician taking the time to look at this discussion thread and reply with his perspective. I hope this (or even another diagnose and replace) takes care of the problem enough to where I feel its no longer an issue; otherwise, Chrysler will probably be hearing from me to take it back. As an Engineer myself, I appreciate the time and trouble you go through to find out the problem on a sophisticated piece of Engineering. And...I also know the first or second wave of technicians at a corporation can feed you useless information...when issues finally get to me at my company, I can't believe some the answers given to customers before me on the product I developed.
#160 of 202 Re: Vibration with Hemi at 70-75 MPH
Mar 21, 2008 (7:13 am)
Well, got the new rear driveshaft today and found out something interesting on the new shaft vs. the old shaft in this particular Jeep (same part number too). The balance weights are VERY different, smaller weights and more of them (looks like someone is paying attention to the driveshaft balancer now). I ran it on the highway with my sirometer (basic frequency meter) and found NO vibrations at 55, 60, 65, 70, and 75mph...looks like this forum put me in the right direction on the repair. Vehicle is going over to Make Ready for a cleaning and will test it one more time before I close up the ticket.
#161 of 202 so is this problem only w/ 4wd vehicles ?
Mar 24, 2008 (7:09 pm)
we plan on leasing a 2008 GCL, rwd. but i'm very concerned after reading all the hardships everyone here is/ has encountered. i did test drive a rwd hemi ltd, but didn't notice any vibrations. it could've been the fact that it was a short highway section (3 miles) or the fact i was so enamored w/ the rest of the vehicle. has anyone here had this problem w/ a rwd vehicle ? tia, for any input.
#162 of 202 Re: Jeep Grand Cherokee Hemi Vibration [jaybee5]
Apr 06, 2008 (4:56 am)
Hello, so I have some more news about vibrations. I had tires balanced and then my repair service took the shaft for rebalancing. Everything was OK and according to standards, no problems found (yes the service confirmed vibrations are problem with my car). If your service claim vibrations are caused by wheels, ask them to raise the vehicle with wheels off and check again.
The repair service then did more detailed vibration analysis and probably took apart transmission and front drive train for tolerances check (if they do warranty fixes they are not obliged to tell you what they did and how they fixed it..). They found no problems again. So the official message is "we found no problems and vibrations you feel may be caused by switching the HEMI cylinders". I dont believe that, because vibrations neither depend on engine revolutions nor switching cylinders. As written before, I believe they depend on actual speed of car, thus are related to parts that are affixed to shaft and wheel axis.
When I got the car back, it seems the problem is partially fixed, so I think it may be improper mounting during manufacturing process - dismounting and remounting may partially fix it.
I am not quite sure what to do next. Either I can take independent court analyst and cooperate with him in court actions against the service, or I can wait until the problem appears in Technical Service Bulletin and then have it fixed under warranty. I would not risk paying by myself to change front or rear drivetrain as I am not 100% sure it is the cause of problem.
#163 of 202 Re: Jeep Grand Cherokee Hemi Vibration [jaybee5]
Apr 06, 2008 (5:28 am)
Vibrations (caused via harmonics) can be caused by changes in engine operation (among other things) - RPM, Exhaust pulses, cylinder changes, accessory pulleys, A/C compressor, etc. There are quite a few things in and on the engine that can easily change the harmonics and cause a vibration. Re-mounting a tire can change the driveline harmonics if one (or more) tires had too much weight - excessive road force can also cause a low frequency harmonic (vibration).
Checking the vehicle in the air changes driveline harmonics as the tires are now free spinning (no friction from the road) and driveline angle is different. It also changes suspension and driveline geometry. Checking for vibrations at a specific speed requires that the vehicle be on the road at ride height. Can it help - if the tire/wheel is severely out of round...you'll see it...but other than that - having it up in the air isn't going to help much.
As for repairs under warranty - the dealership does have to inform you of what was repaired - any parts used for warranty work have to be documented on the work order anyway for warranty claims to be paid. If there was nothing on it, request a copy of the technicians notes on the shop ticket.
I'm not trying to defend the dealership but as a service tech (and dealing with one of these specific issues), it's definitely not an easy one and claiming one fix for every case isn't the correct way about it. I've gone over a vehicle now with a runout gauge on just about every point on the driveline - everything is well within normal limits and now have requested that a Chrysler Engineer/Field Tech come out and look at it with me. I'll post what we find but remember, a fix for one specific case isn't going to necessarily be the one for all.
Apr 19, 2008 (4:43 am)
Hi! I from Russia (g. Kirov).
Has bought Jeep Grand Cherokee Limited 2000г. 4,7л. a box the automatic device.
We in city do not have service on these machines.
At me a problem with a back suspension bracket + with a back reducer.
Very much you I ask give the reference to a site where is detailed instructions and step by step diagrams for all workshop procedures of repair of these units in figures or photos with the description of work.
If you have opportunity I shall be very grateful.
Yours faithfully to you Oleg. e-mail: GELO2006inbox.ru
Excuse for bad English.
(Здравствуйте! Я из России (g. Kirov).
Купил Jeep Grand Cherokee Limited 2000г. 4,7л. коробка автомат.
У нас в городе нет сервиса по этим машинам.
У меня проблема с задней подвеской + с задним редуктором.
Очень вас прошу дайте ссылку на сайт где есть подробное пошаговое описание ремонта этих узлов в рисунках или фотографиях с описанием работы.
Если у вас есть возможность я буду очень благодарен.
С уважением к Вам Oleg. Свой e-mail: GELO2006inbox.ru
Извините за плохой английский.)
#166 of 202 JGC 2001 Limited Shakes & Vibrates at low speeds
Mar 26, 2008 (9:19 pm)
JGC 2001 Limited Shakes & Vibrates at low speeds when making turns. It doesnt shake when just stopped in drive or idling, only when turning, or turning the wheel. What is going on? I know there are tons of postings on this but is there any fix that can be done?
#167 of 202 Re: so is this problem only w/ 4wd vehicles ? [humph]
Sep 04, 2008 (4:40 pm)
I just puchased a new (demo) 2007 GC CRD that has Quadra Drive II with 9000 miles on it. At approx. 38 MPH up to like 72MPH I have a vibration. I do not feel the vibration in the steering wheel but can feel it in the seat bottom. The tires were balanced and are perfect, Jeep replaced the rear drive shaft, no differnce at all. Great Jeep tech went for a ride with me and claimed that the vibration is routine and typical; he really knew the vehicle and has over 19 years with Jeep service. He was willing to chat with Jeep engineers to see if there was any tweaking that might be able to be done to help the issue. I love the vehicle but the vibration does bother me, I do not have such a vibration in my 06 Liberty CRD.
#168 of 202 Re: Jeep Grand Cherokee Hemi Vibration [rkbintx]
Sep 04, 2008 (9:37 pm)
To Whom It May Concern:
I started this post years ago and have spent countless hours and miles trying to find the problem with my 40,000.00 vibrator. I thought about 30,000 miles ago I found the problem. I was told I had "flat spots" in two tires. So I replaced the POS Goodyear tires with a larger, heavier tire by Cooper. I thought all my problems were solved. The vibration was gone, and i posted a message years ago about it. Come to find out the tires I put on my jeep were up for a recall due to seperation and cracking in the rubber...just my luck! Cooper offered me a large credit to a tire of my choice. I went with a Michelin and immediately noticed the good ole vibration again! I was pissed to say the least. Since Gustav was beating down our door and the wait to have the tires checked was 5 hours I sucked it up and drove back to Texas with a back massage. The light at the end of my tunnel came when I went to Discount Tire and informed them of my situtation. Jose the service guy informed me of the machine they use to balance tires and rims. He told me each Discount Tire only has one machine ( its called the 9200....or something like that). What the machine does is find the heavy spot on the rim and the heavy spot on the tirs and offsets each heavy spot by rotating the tire 180 degree from the heavy spot on the rim. I thought it was hard to believe but I will testify it works. My 05 Hemi has never been this smooth. If this interest anyone and a Discount Tire is within reach ask for a "computer spin balance" AND "Computer Ride Match". This was the only time i ever spent 96 dollars on balancing tires and it was worth every penny!!!!! Also after changing my tires to Michelin I am avg. 23-24 MPG highway traveling 65MPH.
P.S. IN MY OPINION******** "Started noticing a vibration at between 70-75 MPH I had never experienced before. ....Finally, after a third time at the dealer, they mention its the MDS feature. When only 4 cylinders are running, a "harmonic change" in engine operation is introduced and this causes the vibration (however, it seems odd that only 4 cylinders would be running when I believe I am accelerating). The Chrysler tech rep. said this is within normal operating parameters," ********* ummm yeah.....it states in the manual the engine runs on 4 cylinders between the speeds of 40-60MPH........and only after it travels 5 miles.........yeah.......I think the Chrysler tech rep needs to read the manual.......again thats just my opinion.