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The QTI and QTII transfer case is essentially an electronically controlled center differential, more like an electronically controlled version of the Torsen center differentials Audi started using decades ago (that system was based on clutch packs that operated like hydraulically driven rear LSDs). Because it's electronically controlled now, they can send up to 100% of power front or rear in a fraction of a second. They advertise it as 'disconnecting' the front axle under normal conditions (presumably in AUTO/SPORT modes). This probably helps fuel efficiency.

Just my conjecture, as I haven't found any 'white papers' on the current system, but it seems like if you select SNOW, SAND/MUD, or ROCK mode, it probably activates the front axle upon selecting the mode, possibly at 50/50 (where it will otherwise activate the front axle automatically when it detects rear slip in AUTO/SPORT modes). From what I've been able to glean from various videos, cars with the rear eLSD will automatically activate the rear eLSD if it detects L/R slippage at the rear (locking it, effectively) in SAND/MUD mode, and engages the rear eLSD more quickly in ROCK mode (which requires 4 low engaged). I've also read that SNOW mode is NOT what most people might expect: It's designed to promote neutral handling, and thus will NOT lock the rear eLSD (seemingly EVER), so if you're in a low traction environment (ie stuck in the snow or driving uphill in loose/deep snow, etc) you want to be in SAND/MUD, or ROCK mode. SNOW mode is meant to promote 'stability' over anything else (ie pulling out to pass on a snowy two land road, etc).

Watching the videos of the WK2 (which also had the ZF rear eLSD) vs the WL, it's pretty clear the system was significantly FASTER to engage the rear eLSD on the WK2. This seems like a mistake, even a 'defect', but it may be by design. I much prefer the faster-engagement of the WK2, for sure.

But, with regard to the center 'diff/transfer case', it seems like if you had the keys to the computers, you could program a 'drift' mode that would lock it in RWD, and also lock the rear eLSD, and remove or dial the stability control system waaaaay down (lots of sports cars have this programming, with modes allowing more drift angle, etc by the driver).

Unfortunately, the software systems are now so secure that aftermarket tuners can't get into that system to add such a thing. Living at a ski resort in Wyoming, I would soooo love it if we could have a 'drift' mode, but as it stands, Jeep doesn't even allow traction control to be fully disabled, which is annoying for off road use as well. When the conditions are good, I just drive my old manual transmission Xterra with its fully defeatable traction control in 2wd with the electronic rear locker engaged (have to put it in 4 low to engage it, but if you shift back to RWD, it stays engaged :cool: ) for shits and giggles. As it is, though, the WL is a 'fun sponge' in the snow. If anyone ever offers a way to enable a 'drift mode' on the WL, I will be the first to buy it.

On the WK2, someone figured out that you could pull the center console cupholders up and install a 'kill switch' on the purple wire running up the tunnel and it would fully deactivate the ABS and stability control (once ABS is off line, the stability control can't operate either). Hopefully some resourceful person at least figures out how to do that on the WL at some point, and maybe there's a way to kill the wire to the center diff that would leave the front axle disconnected as well, if RWD is the 'default' mode.

As a car guy who likes manual transmissions and complete control over things, I'd really like those options.
 

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I will be fully testing out the transfer case to see how it works, much like how I did with my WK2

My guess is the F05 fuse will make it RWD, but that may cause a bunch of other problems.

The transfer cases in jeeps don't require slippage to send power, lots of time it's just done by throttle input.

But since the Trackhawk had selectable modes with this transfer, its a matter if getting the parts and enabling them in the BCM and DTCM
I look forward to hearing what you find. I really want to find a way to completely defeat stability control, and would love to lock it in RWD too 馃榿. It would seem, like diffusing a bomb, if you can put a kill switch on certain wires (effectively cutting them), you could have a 'crude' version of what could otherwise be done with code. I'm sure it would trigger all manner of error codes and warnings, though, and could possibly require a dealer visit to reset in some cases.

To wit: my air suspension once defecated the mattress after towing snowmobiles, sending the rear sky high and the front to low rider setting after the trailer was detached, and I couldn't reset it. I had to drive it like that until the dealer could look at it and reset it. So, be prepared for things like that... but please try! 馃槣
 

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No. It's gone. So is the "SRT". Any next generation "performance" Grand Cherokee, if one ever comes to be (I doubt it) will most likely be electrified just as Dodge is doing with their performance vehicles.
They have said they're 'considering it'. The SO Hurricane, when released, should be quite fast on its own. Based on my calculations, we could see a near 4.5 second 0-60 time from publications like car and driver.

There won't be another Hellcat or V8 performance model, but they could create a HO Hurricane GC, or possibly a SO and/or HO 4xe iteration as well, but I bet that won't come until the mid life refresh closer to 2028 MY based on interviews/statements from Jeep and this 'leaked' production schedule below (which looks consistent with Stellantis internal documents). A performance model would probably be for the 2 row, not the 3 row, but that's just a guess.

They're surely playing with test mules, but there haven't been any confirmations beyond 'it's possible' from Jeep directly (that I've seen). I'd be shocked if there weren't a group of engineers tasked with 'see what you can do', though.

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If everyone did their homework like you seemed to have done, perhaps there would be aftermarket tuners that would allow this. Unfortunately, almost nobody digs in as deep as you have. Have you ever tried asking anyone at the dealership a question about the 4-wheel drive systems in any of the Jeeps? They're stunningly clueless every time I've asked over the years.
The dealer seems only concerned with making their computers happy. Any further understanding of anything is superfluous knowledge from what I can tell.

As far as tuners go, though, it seems like the security imposed on the current gen of electronics is pretty strong, so the dev time to hack that is apparently vastly higher than it used to be. That being the case, it鈥檚 sort of a waiting game, and I鈥檇 guess we won鈥檛 see anything for our WLs unless the security can be hacked on a Wrangler and copy pasta鈥檇 to juxtapose it on the WL, Since the WL market is generally not spending a fraction of what Wrangler owners do on modifications.

Hell, almost two years in and a lot of us would be happy to modify our vehicles to perform as advertised.
 

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Its not so much hacking, Unless the Jeep uses GPEC5 PCM HP Tuners has supported tuning jeeps for a long time. 2015+ have their PCMs locked but its easy, HP Tuners unlocks your original or you buy a used one and get it unlocked.

Security has already been "hacked" on Wranglers, just not one ones with GPEC5, so that would be some vehicles starting in 2021 (All 4xe's are GPEC5)
I know very little about the security protocols they're using, but one of the things I recall reading about the ZF eLSD and transmission (and I assume they make the transfer case?) is that they were touting their 'high security network'. What it is I have no idea, but they're proud of whatever they did to that end apparently. My cursory knowledge of what manufacturers have been doing throughout the vehicles is only that they've all been taking increasingly serious steps as they've added more and more autonomous features - increasing security in the interest of safety and liability.
 
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