Trail Recon T-Case Failure

axhoaxho · Jun 30, 2023

TrailRecon (Brad) has a buddy OVRLNDX (Macro), who also has a Rubicon 392. Both tow a trailer, and both work their vehicles hard.

Sometimes they drove their Rubicon 392s to the off-roading trips together. Macro also drove his Rubicon 392 (towing a trailer) to Mexico at least a couple times, iirc.

Anyone knows if the transfer case of Macro's Rubicon 392 is holding up okay?

https://www.youtube.com/@OVRLNDX/videos

LTZ470 · Jun 30, 2023

axhoaxho said:
TrailRecon (Brad) has a buddy OVRLNDX (Macro), who also has a Rubicon 392. Both tow a trailer, and both work their vehicles hard.

Sometimes they drove their Rubicon 392s to the off-roading trips together. Macro also drove his Rubicon 392 (towing a trailer) to Mexico at least a couple times, iirc.

Anyone knows if the transfer case of Macro's Rubicon 392 is holding up okay?

https://www.youtube.com/@OVRLNDX/videos

View attachment 23136

I messaged him, will revert back when I hear from him…

stumblinhorse · Jun 30, 2023

You want your transfer case to hold up just use it properly…. Do not head off road in 4H auto…

Hoghead · Jul 1, 2023

stumblinhorse said:
You want your transfer case to hold up just use it properly…. Do not head off road in 4H auto…

Or in 4 high. I only off road in 4 low for the last 25 years.

stumblinhorse · Jul 2, 2023

Hoghead said:
Or in 4 high. I only off road in 4 low for the last 25 years.

Definitely. The mp3022 t-case locks 50/50 in 4-low. No clutch use after that at all. They’ll never wear out.

Mouse · Jul 7, 2023

Just watched a video that litebright did on putting an atlas in their Jeep and it came out pretty clean.

after that I went to the advanced adapter website and found the kit to put an atlas in the stock 392.

Jeep JL 392 8HP75 & 4xE Hybrid TO ATLAS

www.advanceadapters.com

im not saying I hope my t-case blows up, but if I’d does why not go all the way. Especially if the warranty is done.

Marmot · Jul 7, 2023

I got a price quote yesterday on the swap. $7500ish installled. After having the case have the issue on the 4th on a mild forest service road (black mountain in socal) I figured its time to start looking. 6200m on jeep, second time out on the dirt. It shut off the front axle when I tried 4low and popped up the service 4x message. Shut the jeep off for 10 min or so, didnt put it back in 4low and it seemed to be fine to get off the road.

axhoaxho · Jul 7, 2023

stumblinhorse said:
Definitely. The mp3022 t-case locks 50/50 in 4-low. No clutch use after that at all. They’ll never wear out.

Thank you for the information.

Does the transfer case in the 392 'locks 50/50' in 4-high also?

stumblinhorse · Jul 7, 2023

axhoaxho said:
Thank you for the information.

Does the transfer case in the 392 'locks 50/50' in 4-high also?

there are 2 4-high settings in the 392. 4H auto and 4H part time. Neither will lock 50/50. 4H part time will have less wear on the clutches Off-road. 4H auto is only to be used on road/hard surfaces.

axhoaxho · Jul 8, 2023

stumblinhorse said:
there are 2 4-high settings in the 392. 4H auto and 4H part time. Neither will lock 50/50. 4H part time will have less wear on the clutches Off-road. 4H auto is only to be used on road/hard surfaces.

Thanks, that is good information. With that in mind, it would help me to choose the right modes accordingly.

BarneyM · Jul 8, 2023

stumblinhorse said:
there are 2 4-high settings in the 392. 4H auto and 4H part time. Neither will lock 50/50. 4H part time will have less wear on the clutches Off-road. 4H auto is only to be used on road/hard surfaces.

I believe that the differentials are locked together in 4H Part Time. Try this. Get the Jeep on a dry surface with good traction, concrete or asphalt. Place the transfer case in 4H Part Time and try to make a sharp turn. Things will bind up very quickly! Same as a regular transfer case in 4 wheel drive. Please don't ask me how I know this...

onfire392 · Jul 8, 2023

BarneyM said:
I believe that the differentials are locked together in 4H Part Time. Try this. Get the Jeep on a dry surface with good traction, concrete or asphalt. Place the transfer case in 4H Part Time and try to make a sharp turn. Things will bind up very quickly! Same as a regular transfer case in 4 wheel drive. Please don't ask me how I know this...

A guy tested the electrical output sent to the clutches in 4A, 4P and 4L. 4L was locked 50/50. That’s the safe place. 4P was closer to 50/50 than 4A but was not locked. Oddly, it was more throttle percentage based (primarily) and slip secondarily. You should notice a binding change going into 4P in tight turns as it senses rotation delta between tires. Offroad I’m going to use 4L to bypass the clutch slippage nonsense.

Hoghead · Jul 8, 2023

I wonder if the 4h in off road mode changes anything? Other than shift points and torque.

Cali392JL · Jul 8, 2023

LTZ470 said:
I messaged him, will revert back when I hear from him…

Any word from Marco?

axhoaxho · Jul 15, 2023

Brad just realized a nice walk-through video of the 2024 Rubicon 392.

In the video, he has not once, but twice, said, "I mean I'm not trading-in my Jeep anytime soon....."

From the smile on his face, I think what he meant was, "I really want to trade-in my Jeep to this new 2024 392..... soon!"

prodriquez · Jul 18, 2023

stumblinhorse said:
Yes. 4H part time is the correct setting for any “off-roading”. Dirt roads etc, 4H auto is fine.

4H part time does a 1 time engagement and keeps 50/50 front/rear. 4H auto engages the fronts up to 50% as the sensors think are needed, repeatedly. This wears clutches out.

I humbly disagree. 4H part time is the correct setting for Mall Crawling… assuming the parking lot got a little slippery and someone spilled their ice-tea.
4L is for off-road

As for the original topic, he likely wore out the clutch plates because he is towing a very heavy trailer, off-road, for long distances. 4H and 4A do not lock anything and 4L would kill his gas mileage. Alternatively, it could also just be bad luck.

As for the general discussion around swapping a transfer case for an aftermarket… I’ll do it if my factory tcase ever goes out on me AND I can’t get it replaced under warranty.

Until then, I’m thinking a 4-link in the rear or an auxiliary fuel tank.

prodriquez · Jul 18, 2023

4R73M15 said:
Got it. To be fair, early on I did have struggled getting it to engage, especially from 4WPT to N and from N to 4L. It has never been quite right.

Shifting to 4L takes more effort and it is nothing to worry about. Mechanically, there is a lot more going on.

On a positive side, jeep finally released power front seats and side airbags! Maybe there is hope that they will add a little button or dial that will shift between 4 wheel drive modes on the next model.

stumblinhorse · Jul 18, 2023

prodriquez said:
I humbly disagree. 4H part time is the correct setting for Mall Crawling… assuming the parking lot got a little slippery and someone spilled their ice-tea.
4L is for off-road

As for the original topic, he likely wore out the clutch plates because he is towing a very heavy trailer, off-road, for long distances. 4H and 4A do not lock anything and 4L would kill his gas mileage. Alternatively, it could also just be bad luck.

As for the general discussion around swapping a transfer case for an aftermarket… I’ll do it if my factory tcase ever goes out on me AND I can’t get it replaced under warranty.

View attachment 23969

Until then, I’m thinking a 4-link in the rear or an auxiliary fuel tank.

That response was to a question if 4H part time is better off road on mild trails than 4H auto. I have said many times over if you want your t-case clutches to last 4L is the best setting since it is locked as much as in can 50/50. If you want to wear them out, go “off-road” In 4H auto.

guruman · Jul 19, 2023

stumblinhorse said:
That response was to a question if 4H part time is better off road on mild trails than 4H auto. I have said many times over if you want your t-case clutches to last 4L is the best setting since it is locked as much as in can 50/50. If you want to wear them out, go “off-road” In 4H auto.

In every other Jeep transfer case, going back 30 years, with "full-time" the 4h "part-time" setting is locked 50/50, I do not believe that our 4h "part-time" is any different, otherwise how is it different from 4h "auto"?

Not all off-road driving is suitable for using 4L... This is why we have a 4H settings. I agree that driving around in loose/slippery conditions in "auto" would cause wear on the front output clutches.

stumblinhorse · Jul 19, 2023

guruman said:
In every other Jeep transfer case, going back 30 years, with "full-time" the 4h "part-time" setting is locked 50/50, I do not believe that our 4h "part-time" is any different, otherwise how is it different from 4h "auto"?

Not all off-road driving is suitable for using 4L... This is why we have a 4H settings. I agree that driving around in loose/slippery conditions in "auto" would cause wear on the front output clutches.

4H part time is not locked 50/50. It will slip the front based on throttle. It is a bad choice by the programmers. But it is a fact…

The simple difference between auto and part time is part time starts 50/50 and slips back to 20/80. Auto is the other way. With most rear to start and adds to the front. 4L is the only locked mode.

I don’t know if you meant all Jeeps. But the full time 4WD jeeps haven’t been been locked 50/50 for a while. My JGC has the same t-case as a 392. It is quadra-trac 2. Not locked, there is no full time or part time setting….