New Grand Cherokee L - Flat Tow???

[04266832]

Good morning, folks.

How is everyone wiring up the tail lights? I haven't found any specific info on the GC-L but some of the mention's I've seen show the wiring running into the top of the lift gate. Some show it going to the tail light housing in the body. I haven't been able to find a definitive wiring guide.

Thanks in advance.

[RedCatcher46]

Originally Posted by 04266832

Good morning, folks.

How is everyone wiring up the tail lights? I haven't found any specific info on the GC-L but some of the mention's I've seen show the wiring running into the top of the lift gate. Some show it going to the tail light housing in the body. I haven't been able to find a definitive wiring guide.

Thanks in advance.

Several options ETrailer.com has some wiring kits and videos on how to install and route wiring. Our 2021 L has wiring routed to tail lights then behind bumper facia to opposite side tail light. I listed some part numbers in a previous post. I spoke to a Jeep rep at Winnebago Rally last week. I asked about the status of a Mopar part number for an OEM flat
tow wiring harness. He made a phone call, then said he would get that number to me and asked if I would post it here. Not holding my breath

[jmfixitman]

Originally Posted by voltdoc

Same idea I used:
https://myquantumdiscovery.com/2021-...stallation#ABS

Mine is an early version of the Roadmaster on an Overland, is yours the RM or BlueOx baseplate?

Well that would have saved me a lot of brain power... Lol. Yes mines the Roadmaster. The Summits grille was a little challenging, but it came out nice and tows great!

[jmfixitman]

Originally Posted by 04266832

Good morning, folks.

How is everyone wiring up the tail lights? I haven't found any specific info on the GC-L but some of the mention's I've seen show the wiring running into the top of the lift gate. Some show it going to the tail light housing in the body. I haven't been able to find a definitive wiring guide.

Thanks in advance.

I couldn't find a specific one for the GCL. I purchased a GCL trailer light kit that had the plugs for the taillights so I wouldn't have to cut the factory harness. I cut those off and used them with a 24' four wire trailer lighting kit. Put the wire in some 3/8 wire loom and ran it from the front plug over the wheel wells and tucked and zip tied it to the passenger side undercarriage/rocker panel. Then used a Hopkins diode kit to connect to the taillights.

Hopkins 48955 Towed Vehicle... https://www.amazon.com/dp/B0002Q81Y4?ref=ppx_pop_mob_ap_share

[Lsulpy]

Hey Jason, we have a Entegra Accolade 37k that looks similar to your Seneca and a 2022 GC-L Summit we just started towing. Have you had any issues with your Overland staying charged while towing? Are you using a charger or just the Coach Umbilical cable to the Overland battery? Does your steering stay active in transfer case neutral the whole time towing? Voltdoc's spreadsheet has been invaluable for this process.

[RedCatcher46]

A hot wire running from the coach via the umbilical to the TOAD then wired to the battery works well for us. Yes, when you properly shut down your car, the steering remains active. We have flat towed our Overland L for nearly 10,000 miles and a couple dozen hook ups and disconnects. Car tows like a breeze. You are correct, VoltDoc’s instructions are invaluable in getting it done correctly. You won’t even know it is behind your Integra. Suggest you use Air Force 1 for braking. Freightliner chassis built after mid year 2022 will have a brake air line run to the rear of the chassis. That will make AF1 installations much easier.

[Lsulpy]

Thanks for the quick answer. Ours is early 2022 so we went with the Air Force One and had to add the coach side isolator tank. We did the hot wire from the umbilical to a breaker then to the Summit L battery and it seems to work well so far. I was curious if it would keep the battery charged after a day of driving. The steering stayed active when we tested it in a parking lot and then on a 7 hr trip but the wheels didn't seem to be turning as much as they were at the end of the trip back and I didn't think to check if the EPS was still active due to some other issues we were having with the steering. It was still in transfer case neutral and I was thinking that equaled tow mode and active EPS.

[JeepinJason]

I would wire it directly to the battery. I use the RVi battery charger on both of our vehicles... https://rvibrake.com/pages/towed-bat...er-plus-videos

We also tow a lifted 2021 Jeep Wrangler Rubicon on 37" tires. The tires on the Wrangler turn/steer much easier than the ones on the Grand Cherokee L. The Grand Cherokee does not track as easily and seems to drag a bit more on tight turns. I had one of my kids stay in the Grand Cherokee in our gravel storage lot to ensure the wheel was still free to ensure it was not locking up.

[SuperGewl]

Originally Posted by Deek

We are looking at new 4 x 4 Jeep Grand Cherokee L (three row seating) which dealers are now getting. If buying, we would prefer the regular size, two row seating version, but we’re told that those vehicles won’t even be able to be order until the end of August with expected delivery by the end of October.

I have been burned by the “death wobble” issue before - and decided to sell a perfectly good brand new 2018 GC Summit when FCA had no GC fix for the new EPS system which changed without our realizing it in model year 2016. This change, of course, resulted in the dynamic of the death wobble when FCA changed from a hydraulic steering system - which allowed the GC to properly track with the motor home - to the current electronic steering system - which opens the door to the death wobble when the computer bus shuts down the EPS after the car is shut off and does not allow seamless tracking of the tow vehicle with the motor home - especially in slow driving turning situations and uneven pavement.

Have always loved the Grand Cherokee Summit (a 2015 model I had and flat towed with my Dutch Star 4369 was the hands down best SUV I have ever owned), but could not and would not tolerate the uncertainty of the death wobble risk in a new vehicle that expensive. In my humble opinion, FCA never, ever treated this issue with the seriousness it requires - and despite the wiring harness “fix”, I am not persuaded enough to buy the exiting model.

Fast forward to now. FCA is releasing the stretched “L” model and dealers are getting them. We test drove an Overland model with 4 x 4 yesterday. OMG, what a ride! A whopping 62K price tag, with absolutely zero incentives right now, but, crazily, worth the entire price!

Allowing ourselves to get just a wee bit excited about the possibility that the new Grand Cherokee L could possibly have the death wobble issue fixed - assuming FCA would pay some attention to the RV market for its vehicles, especially with their direct knowledge of the many death wobble reports that have been given to them by GC owners and the NTSB - I am wondering if, by chance, the death wobble problem is somehow fixed in the new GC.

For this kind of money, I asked the sales manager to run the issue up the line to see what they could advise on this question. Response, given this morning, is that the EPS system on the new Grand Cherokee L is “completely different from the older vehicle”. I asked specifically how it’s different and does this mean that FCA, knowing about the past death wobble problems, has, in fact, finally and definitively resolved the death wobble in the new GC.

As you can imagine, that information is unknown by the reps that were contacted.

So I’m wondering what our Forum might be able to tell us on this. Does anyone have any info out there that would help to shed light on this inquiry.

All answers, comments, information will be greatly appreciated for all of us.

Thanks!

Deek

Death Wobble is here to stay. 2 things cause it, EPS(electric Power steering) and your particular tow bar & base plate setup. So if you correct your setup yo should not have to worry about this "Death Wobble" You are not going to get rid of the EPS because most cars and trucks come with it.
I have a 2014 Jeep Cherokee Trailhawk and have never had the issue because my tow bar setup and base plates setup are done correctly.:

[RedCatcher46]

If someone is saying that “death wobble” is here to stay with the GCL Overland or Summit I must disagree. We have a 2022 Grand Cherokee L Overland. I’ve flat towed it nearly 9,000 miles with a couple dozen hook ups and disconnects. It tows like a dream. We drive a 2022 Winnebago Forza 34T. Pulling with our MH we honestly don’t know the car is back there. We use a Roadmaster Nighthawk tow bar. We have our hitch set up so it is perfectly level when connected. Steering stays active. Our power lead from the MH is wired to keep battery charged. No complaints at all.

[JeepinJason]

Death wobble can be caused by several worn-out steering or suspension parts, although out-of-balance tires, bent wheels, loose wheel bearings, a bad alignment, low tire pressure, a bent tie rod, as well. Pulling it behind a motorhome can add to the stress on some of these items but many of the vehicles that get death wobble behind a motorhome will have the same symptoms driving it down the road.

[voltdoc]

SuperGewl responded to the original post Deek made which was well before a baseplate even existed for the then new GC-L. At that time there were many unknowns.

Now there are at least two baseplate makers with many 2021-22 GC-L Overland and Summits being towed sucessfully every day.

In my case, like RedCatcher46, between October 2021 and May 2022 I have towed my 2021 GC-L Overland over 9000 miles with 40 or 50 hook/unhook sessions with no issue with death wobble - or anything else for that matter.

IMO the biggest concern with the GC-L is the Electric Park Brake activating and locking up the rear wheels. However by understanding what activates the EPB and following the procedure referenced elsewhere in this thread, that issue can be effectively avoided.

Back to death wobble, from my own research on the subject, JeepinJason has a point that wear and tear plays a big role, so as our vehicles age perhaps that will have an impact. Regarding SuperGewl comment that EPS causes death wobble is not entirely accurate, while Jeeps with EPS tend to have the problem, the root of the issue is if EPS is not active while towing.

Jeep has allegedly developed software algorithms for the EPS that actively seek to prevent death wobble. But if the software isn't active when the vehicle is being towed it does no good.

On the GC-L EPS is 100% active while towing. You can test this, the wheel will be "soft" (easy to turn) while the vehicle is in tow mode.

On prior models before the GC-L, this may not be the case. There is a plethota of confusing info floating around regarding various attempts by Jeep to fix this by developing a "harness" to keep EPS active while towing. Depending on the year and model there has been some success with this, but there were also a lot of reports regarding misunderstanding of what the harness does and improper installation by dealers.

Bottom line regarding death wobble - the GC-L is as protected as it can be by software, just keep a close eye on your suspension parts and fix any issues sooner rather than later.

[jmfixitman]

I don't think you can compare and reference any older Jeep models to the GCL. For many reasons as already mentioned, it's a different animal. We have a 2022 GCL Summit and love it. Used the Roadmaster baseplate and nighthawk towbar and have had no problems at all. Also use the Air Force One for braking and charge through the umbilical.

[pattypom]

I spoke to the mechanics figuring the salesmen know squat. The mechanic said the GC with third row seats can be flat towed. I had my jeep in the shop for a repair and showed him where they installed my tow equipment in the front end of my 2015. We looked at the 2022 and wasn’t so certain where to hook up the tow equipment. Heck I was afraid to pull the trigger on a new jeep. Keeping the old one. It has under 50,000 miles.