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-   -   New Plan - Jeep Grand Cherokee EPS Wobble (https://www.irv2.com/forums/f85/new-plan-jeep-grand-cherokee-eps-wobble-360864.html)

BPoland 03-30-2018 03:28 AM

We have had the 2016 GC Limited since early February 2016. We have towed it thousands of miles, and have had two instances of wobble. Both were starting from a dead stop with a left hand turn. I stopped and restarted and that was it. I have never had it occur at highway speeds and have only heard of 1 person reporting that it did. Great car. Great towed. That being said, if it ever occurs at highway speeds, itís gone.

Best of luck to you. Enjoy the Summit.

Ready2Travel 04-01-2018 09:55 AM

Quote:

Originally Posted by Hmf23 (Post 4110442)
While I've been watching this thread closely and waiting for the tow harness wiring to be made available we still purchased a 2018 GC Summit. Fully set it up and planned to tow and take it easy as we start using it as a Toad. Reading it seems most incidents were with slow speed tight turns and uneven surfaces, so I'm really watching whenever those may exist. Currently on a week long trip to Disneyland, we l ft last Friday with 3 days in Santa Cruz and then they Disneyland. Not one issue yet from Sac to Santa Cruz and the. South to Anaheim, tomorrow we make our way home. So I'm not saying the issue does or doesn't not exist just saying so far so good without any harness installed that I may know of.

Same here, no problems so far with a 2018 Limited GC. Made a trip south beginning In Nov, 3000+ miles, hooked/unhooked about 15 times. So far 0 issues. Our Limited has the offroad package (air suspension plus wider tires plus skid plates) that may or may not make a difference.

lass 04-01-2018 05:14 PM

For everyone who has read through the 2 threads on the GC wobble we have always said that it is intermittent but does happen on occasion. From my last contact with corporate the response remains the same that engineering is working on a solution. Iím certain that it will be released but I have decided the go a different path with the new Wrangler JL.

Iíll continue my contact with Jeep corporate and FMCA and report status as I receive it.

Las

harleyjt 04-01-2018 05:44 PM

New Plan - Jeep Grand Cherokee EPS Wobble
 
What's interesting to me is that it doesn't seem like the EPS system would be much different than conventional hydraulic system. If you think about it, neither system furnishes power assist with the engine off. Both systems are stiff. So why do we need a harness to power up the EPS when towing? We've never had power assist on the toad before and it's always worked fine. I've only toed my 2017 Grand Limited a little less than 1000 miles and so far so good.
jt

jharrell 04-01-2018 07:25 PM

Quote:

Originally Posted by harleyjt (Post 4115276)
What's interesting to me is that it doesn't seem like the EPS system would be much different than conventional hydraulic system. If you think about it, neither system furnishes power assist with the engine off. Both systems are stiff.

My understanding is the EPS systems have a safety clutch that disengages if somethings not right so you can manually steer. If power is off this clutch is also disengaged so now you have little resistance from back driving the steering. The harness energizes the EPS which engages the clutch.

Its actually kind of difficult to find information on the jeep EPS design, but it look like a dual pinion design where a electric motor drives a second pinion on the rack through a worm gear and clutch. Seems like it would actually be very difficult to turn the wheel if the clutch is engaged trying to back drive the motor through a worm gear.

Hydraulic systems don't need a clutch and just offer some resistance when off due to pushing the fluid through the open control valves.

rpasetto 04-01-2018 07:32 PM

Quote:

Originally Posted by harleyjt (Post 4115276)
What's interesting to me is that it doesn't seem like the EPS system would be much different than conventional hydraulic system. If you think about it, neither system furnishes power assist with the engine off. Both systems are stiff. So why do we need a harness to power up the EPS when towing? We've never had power assist on the toad before and it's always worked fine. I've only toed my 2017 Grand Limited a little less than 1000 miles and so far so good.
jt

There's an inherent damping in the hydraulic system which is not present in the solenoid -controlled EPS systems; i.e. the fluid in the former systems resist rapid movements somewhat like the fluid in a shock absorber. In the latter systems, at least on the Cherokee, the software in the EPS computer acts to reduce wobble. The Cherokee-wobble-fix turns the EPS on for this software algorithm to work. Other vehicles from Ford and GM with similar EPS systems have had issues as well. Although all steering systems may feel "stiff when the vehicle is not moving this characteristic changes as speed develops.

Many with Cherokees towed theirs for thousands of miles before having a wobble event. These have been going on since the first 2014 Cherokees took to the road in tow behind motorhomes. I suggest you look through some of the threads in the many Cherokee forums as well as here on IRV2. Here's one thread here worth reading thru: https://www.irv2.com/forums/f85/sever...ee-240620.html

lass 04-04-2018 09:53 AM

Note: I will post this same detail on the 2 main threads that relate to the Jeep Grand Cherokee Electronic Power Steering front end "wobble".

As some of you may be aware, since my first email to the Jeep CEO in early November 2017, I have requested information from forum members who have experienced the "wobble". This information was added to an excel spreadsheet and submitted to Jeep corporate from 2 different directions. It was also sent the John Johnston at FMCA as a 3rd. source.

After approximately 50 email and phone call communications to corporate, the latest information is that Jeep engineering is still performing testing and analysis on 2 possible solutions but we do not have a specific time frame for release.

The FMCA contact has not confirmed any engineering activity to John, so he is going to modify my spreadsheet and needs more information from owners. I will send PM's to "Ol Opa"; "hdridermib"; "13charlie" "Crabby Mike"; "jlr44"; "esaulten"

If you are new to this and have experienced the "wobble" send me a PM and email John directly at FMCA. jjohnston@fmca.com

Remember the Cherokee situation. Owner who added their names to the list, got the upgrade for free.

Las --- as full disclosure, I traded the Summit for a 2018 Wrangler JL Rubicon.
but will continue my efforts in order to find a solution for the GC.

SuperGewl 04-10-2018 05:23 AM

Well now that you have your undies in a bunch you need to fix the problem by looking at your TOAD gear first.
You also need to know that the problem is not just JEEPs but with any EPS Toad.
Start by checking your receiver, you need to extend it out as if you were going to hook it up to the Toad. Then attempt to move it up and down and side to side in the receiver. If it moves or clunks as some might say then you need to fix this. It should not be allowed to oscillate. Install a Quite Hitch.
Next check the ride height of the Toad prior to hook up and then after you have hooked up and aired up the MH. If the Toad ride height is higher after this then you need to lower the tow bar because you are lifting the front of the Toad, or what we call unloading the suspension.
By doing these two things you will help mitigate the Death Wobble in ALL Toads.
Don't shoot the messenger, fix your problem before you point the finger.:angel:

rpasetto 04-10-2018 05:41 AM

Quote:

Originally Posted by SuperGewl (Post 4129903)
Well now that you have your undies in a bunch you need to fix the problem by looking at your TOAD gear first.
You also need to know that the problem is not just JEEPs but with any EPS Toad.
Start by checking your receiver, you need to extend it out as if you were going to hook it up to the Toad. Then attempt to move it up and down and side to side in the receiver. If it moves or clunks as some might say then you need to fix this. It should not be allowed to oscillate. Install a Quite Hitch.
Next check the ride height of the Toad prior to hook up and then after you have hooked up and aired up the MH. If the Toad ride height is higher after this then you need to lower the tow bar because you are lifting the front of the Toad, or what we call unloading the suspension.
By doing these two things you will help mitigate the Death Wobble in ALL Toads.
Don't shoot the messenger, fix your problem before you point the finger.:angel:

Not to disagree with any of the methods you state for proper set up and alignment of the towbar, All towbar manufacturers make these same recommendations for any 'toad' setup.

There is still an inherent wobble tendency in EPS systems. EPS which use servomotors, lack the hydraulic damping inherent in "conventional" PS. FCA/Jeep went through the analysis years ago and developed their patented 'wobble mitigation' algorithm. I suggest you read the many threads about the Cherokee wobble; You'll find information in numerous forums, as well as this one, since 2014.

lass 04-10-2018 01:20 PM

New Plan - Jeep Grand Cherokee EPS Wobble
 
SuperGewl. I certainly hope that you are not referring to my undies being in a bunch because I would find that statement to be offensive.

rpasetto summed it up very diplomatically and that is how we have handled this situation for the past 8 months, but I need to ask. Since your profile says that you have a 2014 Cherokee Trailhawk, are you not aware of the front wobble which was solved by Jeep a little over s year ago. Did you not have a wobble problem and donít need to have the flat tow harness installed.

There are quite a few forum members who are great full that Jeep stepped up with a fix and that is all that Grand Cherokee owners are asking.

Las

rpasetto 04-10-2018 01:39 PM

Just to add to the statement from @lass, Owners of 2014 and 2015 Cherokees got the tow-harness-fix gratis from FCA Jeep because there was nothing in the brochure or owners manual stating that the tow harness kit was required, while it was stated that the vehicles were the ideal towable vehicle (That is the ones with AD2 which has the neutral button). Hopefully the GC owners, at least those who bought theirs early on, may get a similar deal.... when the fix for these vehicles comes along.

As an added caution, many Cherokee owners have been told by dealers "'you don't need the tow harness kit, because ... {variety of B___S___ reasons}". Fortunately only a few owners were gullible enough to believe it. Rest assured, all the towable Cherokees, 2014 and UP, need that kit. When, hopefully soon, FCA comes up with a similar wobble-fix for the EPS-equipped GC's, they'll all need it. [Meanwhile, in my travels, when I see a new-looking GC being towed behind a MH, I give it a wide berth.]

Be safe y'all.

mhudson 04-10-2018 07:02 PM

Quote:

Originally Posted by supergewl (Post 4129903)
well now that you have your undies in a bunch you need to fix the problem by looking at your toad gear first.
You also need to know that the problem is not just jeeps but with any eps toad.
Start by checking your receiver, you need to extend it out as if you were going to hook it up to the toad. Then attempt to move it up and down and side to side in the receiver. If it moves or clunks as some might say then you need to fix this. It should not be allowed to oscillate. Install a quite hitch.
Next check the ride height of the toad prior to hook up and then after you have hooked up and aired up the mh. If the toad ride height is higher after this then you need to lower the tow bar because you are lifting the front of the toad, or what we call unloading the suspension.
By doing these two things you will help mitigate the death wobble in all toads.
Don't shoot the messenger, fix your problem before you point the finger.:angel:



my undies are in a bunch because of jeeps problem, not mine. As i’ve responded before “ no slop in towing equipment”. None. Tow bar perfectly level . As to lifting the front of the toad explain how that can happen when the pins in the baseplate allow for up and down movement and the wheels of the toad are freewheeling?
P;$$ed, yes i am. I have fought this problem through two baseplates, two tow bars and two different braking systems , a usless dealership and an idiot at jeep care. Its the Jeeps eps.

rpasetto 04-10-2018 07:35 PM

Quote:

Originally Posted by mhudson (Post 4131229)
my undies are in a bunch because of jeeps problem, not mine. As iíve responded before ď no slop in towing equipmentĒ. None. Tow bar perfectly level . As to lifting the front of the toad explain how that can happen when the pins in the baseplate allow for up and down movement and the wheels of the toad are freewheeling?
P;$$ed, yes i am. I have fought this problem through two baseplates, two tow bars and two different braking systems , a usless dealership and an idiot at jeep care. Its the Jeeps eps.

Slop in tow equipment and towbars out of level can have other effects, but the "death-wobble" is inherent in the EPS, that is, the lack of damping of a hydraulic system.

One can only guess, that the FCA engineers are well aware of this and are probably in the throws of researching whether adding an hydraulic damper (not possible with the KL Cherokee) or designing a circuit to activate the EPS while towing. However the latter would only work if the software in the EPS of the GC has a "wobble mitigation algorithm" equivalent to that of the KL Cherokee and other vehicles with that platform.

However, while the engineers at FCA may be working on this, marketing is figuring how to spin the facts to sell as much 'iron' as possible and the bean counters are figuring how to maximize profits. Whoever has the say on what FCA will do is anyone's guess.

Safe travels.

BPoland 04-11-2018 10:58 AM

Quote:

Originally Posted by rpasetto (Post 4130682)
Just to add to the statement from @lass, Owners of 2014 and 2015 Cherokees got the tow-harness-fix gratis from FCA Jeep because there was nothing in the brochure or owners manual stating that the tow harness kit was required, while it was stated that the vehicles were the ideal towable vehicle (That is the ones with AD2 which has the neutral button). Hopefully the GC owners, at least those who bought theirs early on, may get a similar deal.... when the fix for these vehicles comes along.

As an added caution, many Cherokee owners have been told by dealers "'you don't need the tow harness kit, because ... {variety of B___S___ reasons}". Fortunately only a few owners were gullible enough to believe it. Rest assured, all the towable Cherokees, 2014 and UP, need that kit. When, hopefully soon, FCA comes up with a similar wobble-fix for the EPS-equipped GC's, they'll all need it. [Meanwhile, in my travels, when I see a new-looking GC being towed behind a MH, I give it a wide berth.]

Be safe y'all.

I had a 2015 Cherokee that I towed for over 4K miles, and never had the wobble. Got rid of the 2015 Cherokee (Lemon Law) and picked one of the first built 2016 Grand Cherokee. I have experienced the wobble twice within 5 mins of each other. Starting out, bumpy hard left hand turn. Came to a stop and wobble was gone. It has never happened at highway speeds. I have heard of 1 person that claimed it happen to them at highway speeds.

I think your comment about giving all GCs a wide berth is a little much. Can it happen? Yup. Will it happen? Maybe. Is it going to be a catastrophic event? Probably not. Will it get your attention, if and when it happens? The pucker factor will go up. :eek:

I like my Grand Cherokee. I donít see it as a towable death trap. If and when FCA comes out with a fix, I will evaluate it and see if itís worth the hassle. I hope I didnít offend anyone. Just tired of ďThe Sky is FallingĒ mentality. Just think, it it wasnít for EPS, this problem wouldnít exist. Ainít modern technology great?


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