New 2024 Jeep Gladiator - Possible FAD or Transfer Case Issue

[mphilleo]

I recently bought a new 2024 Jeep Gladiator Sport and have been really enjoying it. I've been gradually getting miles on it, but still have under 300 miles on it. This morning, I was driving to work in the ice and snow and had a chance to use 4WD for the first time on this Jeep.. I shifted into 4WD high for awhile, then decided to shift back into 2WD high when the roads improved a little. I'd estimate I was going around 30-35 mph at the time, and the 4WD indicator turned off as it should, no flashing or anything unusual. I let off the accelerator for that shift, then applied the accelerator again. It made a terrible rattling, whirring, and buzzing noise, so I got off the accelerator, continued coasting, ensured the shifter was in 2WD high, and applied the accelerator again, and the noise subsided. I made one more successful shift into 4WD high and back into 2WD high without incident by the time I reached work. I've owned Jeeps for years and made sure to follow the procedure in the owner's manual.

I also shared this information with the service manager at the purchasing dealership. He got back to me with this by text:

"The axle disconnect was not fully shifting. While that can be a concern, it's not uncommon both on these and the Fords. Most often, the one-offs as I call them, may be very challenging to duplicate. We could look at it but doubtful a hard trouble code will emerge. Your call...Thanks for reaching out!"

This does seem to match other people's experiences with Gladiators and the FAD. I replied and asked him if he'd recommend changing the transfer case fluid and front differential fluid, since cost isn't a concern for me. He said they certainly could. I'm not sure if changing the transfer case oil is necessary based on what he said, but I'm definitely thinking I'll change the front differential oil. What do you folks think? I've also ordered the Spicer FAD delete kit, but I'm not sure if I should install it until I'm out of warranty. I'm also assuming that requires the Tazer to keep the computer from freaking out?

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[Janster]

Relax my friend…. You have less than 300 miles on it and that was probably the very first time you engaged & disengaged 4WD since you bought it. You did the right thing by contacting the dealership.

It could simply be an issue with engaging/disengaging it for the first time where some of the parts might be a little ‘dry’ (per say) and they didn’t move as freely or as fast as normal.

Go to a dirt road or dirt parking lot… and play a little. Engage & disengage 4WD and also, get it into 4lo also. If you’re still having issues, take it right back to the dealership and you can ‘drive’ it (and show them) while they sit in the front seat.

 

[Hootbro]

There is a lock collar the FAD fork is suppose to slide over the intermediate shaft that locks the axle shafts. Sometime it will partially engage and you will get that rattle. My 2022 Rubicon in really cold weather had that issue on the disengage from 4H to 2H a few times but eventually stopped. Would not show up in warmer weather.

It is a good idea to make sure the fluid is topped on the front diff because most will come with a minimum service fill and not the full service fill. I would also recommend exercising the FAD every couple weeks for a mile or two on level straight road.

 

[mphilleo]

There is a lock collar the FAD fork is suppose to slide over the intermediate shaft that locks the axle shafts. Sometime it will partially engage and you will get that rattle. My 2022 Rubicon in really cold weather had that issue on the disengage from 4H to 2H a few times but eventually stopped. Would not show up in warmer weather.

It is a good idea to make sure the fluid is topped on the front diff because most will come with a minimum service fill and not the full service fill. I would also recommend exercising the FAD every couple weeks for a mile or two on level straight road.

Thank you for the information, I appreciate it. In your opinion, is it worthwhile to drain and refill the front differential and/or transfer case based on this experience? It appears I don't have a front differential drain plug like I did on my previous JK.

 

[Hootbro]

Thank you for the information, I appreciate it. In your opinion, is it worthwhile to drain and refill the front differential and/or transfer case based on this experience? It appears I don't have a front differential drain plug like I did on my previous JK.

Honestly, I would just fill the front diff with gear fluid until it dribbles out the fill hole to make sure it is fully serviced. Unless you ford deep water and/or run it in 4WD day in and day out, the front diff fluid stays pretty pristine. Transfer case does not come into play here either.

Below is a link to the thread I started over a similar issue. Initially thought it was the transfer case and eventually came to understand it to be the FAD and the intermediate shaft engagement. I never pursued the repair mentioned as it seems to resolve itself and was not a constant issue.

https://www.jeepgladiatorforum.com/...se-issue-coming-out-of-4h.77275/#post-1263166

 

[mphilleo]

Honestly, I would just fill the front diff with gear fluid until it dribbles out the fill hole to make sure it is fully serviced. Unless you ford deep water and/or run it in 4WD day in and day out, the front diff fluid stays pretty pristine. Transfer case does not come into play here either.

Below is a link to the thread I started over a similar issue. Initially thought it was the transfer case and eventually came to understand it to be the FAD and the intermediate shaft engagement. I never pursued the repair mentioned as it seems to resolve itself and was not a constant issue.

https://www.jeepgladiatorforum.com/...se-issue-coming-out-of-4h.77275/#post-1263166

Thanks for the suggestion and link. I'm still debating taking the cover off this afternoon and putting in some Pennzoil full synthetic. The main reason is I'm concerned there's wear material and swarf from the FAD collar and intermediate shaft splines rubbing (I'm assuming that's what the noise was).

 

[Uparms]

Can we get some opinions.... does the FAD delete require computer adjustments to eliminate dash warnings or even codes? Can the Mini Taze do it and what other devices will do it? TIA!

Been thinking about RCVs or even a complete new front axle that has the FAD delete.

 

[mphilleo]

Holy smokes @Janster and @Hootbro you guys were spot on about checking my differential fluid levels! I was able to add about 8 ounces to the front diff and about 10 to the rear! Thank goodness I only have 280ish miles on them.

Check these out:

This is the front diff plug. I wiped it before I took a picture, so my finger is included:

Here's a few of the rear. Woof.

I didn't really feel like removing the front diff cover (my Gladiator isn't lifted, so I'd have a tough time without removing the front track bar) since the oil looked pretty good and the amount of debris on the magnet was minimal. So I opted to top it off and roll the dice. The rear was pretty heavy on material and lower than I'd like on fluid. I haven't done it yet but I plan to check the transfer case fluid to be safe.

 

[Hootbro]

Can we get some opinions.... does the FAD delete require computer adjustments to eliminate dash warnings or even codes? Can the Mini Taze do it and what other devices will do it? TIA!

Been thinking about RCVs or even a complete new front axle that has the FAD delete.

There is settings that have to be adjust on the presence or delete of the FAD system. JScan can do modify these settings.

 

[Hootbro]

Holy smokes @Janster and @Hootbro you guys were spot on about checking my differential fluid levels! I was able to add about 8 ounces to the front diff and about 10 to the rear! Thank goodness I only have 280ish miles on them.

Check these out:

This is the front diff plug. I wiped it before I took a picture, so my finger is included:

Here's a few of the rear. Woof.

I didn't really feel like removing the front diff cover (my Gladiator isn't lifted, so I'd have a tough time without removing the front track bar) since the oil looked pretty good and the amount of debris on the magnet was minimal. So I opted to top it off and roll the dice. The rear was pretty heavy on material and lower than I'd like on fluid. I haven't done it yet but I plan to check the transfer case fluid to be safe.

That really is about what I would expect with 300 or so miles as you originally stated. You are still breaking in. So long as there is not actual chunks and just that fine paste sludge on the plug magnet, you are fine. I would not get spooled up on what you have.

Below is my rear diff plug after I swapped out the factory fill after 5K miles. Still normal and will only continue to go down.

 

[mphilleo]

That really is about what I would expect with 300 or so miles as you originally stated. You are still breaking in. So long as there is not actual chunks and just that fine paste sludge on the plug magnet, you are fine. I would not get spooled up on what you have.

Below is my rear after diff plug after I swapped out the factory fill after 5K miles. Still normal and will only continue to go down.

As always, thanks again for your input, appreciate it. The front magnet was what I'd call mostly paste, whereas the rear magnet had paste with fine metal shavings, but nothing I'd say is super alarming or actual chunks.

I took the Jeep for another good jog, about 25 miles, and for part of it, I went down a gravel road. I figured I'd take the advice I got in this thread about exercising the 4WD system. I did notice that shifting into 4HI and 2HI got progressively easier and I never did experience any issues with the front shafts meshing or anything like I first posted about, so that's good.

I'm sure it sounds crazy, but I'm still running the experience on replay in my mind, trying to figure out if it was something I did. I'm 90% confident I wasn't exceeding 45 MPH while doing the shift, so I don't think it was that. The only other thing I can think of is that somehow I didn't have the transfer case shift lever fully seated in 2HI, since it was stiff, although the light went out as I recall. The other possibility is that traction control had engaged at one point and that's what I was experiencing with the noise and vibration, but I don't recall that light on the dash, although it's possible I missed it.

Everything happened so fast, my account isn't necessarily super reliable. I do find it interesting that the front diff was shy by as much as half a pint of fluid, but that may not have made a difference either. I'm curious if there's wear material where the intermediate shaft meets the outer passenger side shaft and now I've raised the fluid level to allow it to wash into the differential area. All of this is a question mark without tearing into things, which I don't plan to do. And none of it really matters, since what's done is done. I'm just working through my disappointment and venting a little bit to anyone who'll hear me out. I'm one of those guys who tries to take care of his vehicles, do things right and by the manual, and this kind of experience cuts a little deep for those reasons.

Sorry for rambling!

 

[Janster]

As always, thanks again for your input, appreciate it. The front magnet was what I'd call mostly paste, whereas the rear magnet had paste with fine metal shavings, but nothing I'd say is super alarming or actual chunks.

I took the Jeep for another good jog, about 25 miles, and for part of it, I went down a gravel road. I figured I'd take the advice I got in this thread about exercising the 4WD system. I did notice that shifting into 4HI and 2HI got progressively easier and I never did experience any issues with the front shafts meshing or anything like I first posted about, so that's good.

I'm sure it sounds crazy, but I'm still running the experience on replay in my mind, trying to figure out if it was something I did. I'm 90% confident I wasn't exceeding 45 MPH while doing the shift, so I don't think it was that. The only other thing I can think of is that somehow I didn't have the transfer case shift lever fully seated in 2HI, since it was stiff, although the light went out as I recall. The other possibility is that traction control had engaged at one point and that's what I was experiencing with the noise and vibration, but I don't recall that light on the dash, although it's possible I missed it.

Everything happened so fast, my account isn't necessarily super reliable. I do find it interesting that the front diff was shy by as much as half a pint of fluid, but that may not have made a difference either. I'm curious if there's wear material where the intermediate shaft meets the outer passenger side shaft and now I've raised the fluid level to allow it to wash into the differential area. All of this is a question mark without tearing into things, which I don't plan to do. And none of it really matters, since what's done is done. I'm just working through my disappointment and venting a little bit to anyone who'll hear me out. I'm one of those guys who tries to take care of his vehicles, do things right and by the manual, and this kind of experience cuts a little deep for those reasons.

Sorry for rambling!

I don’t want to offend anyone by asking…. Have you had 4WD vehicles before?

 

[Janster]

Holy smokes @Janster and @Hootbro you guys were spot on about checking my differential fluid levels! I was able to add about 8 ounces to the front diff and about 10 to the rear! Thank goodness I only have 280ish miles on them.

That was all @Hootbro…….
I just mentioned you drive around a bit.

 

[mphilleo]

I don’t want to offend anyone by asking…. Have you had 4WD vehicles before?

No offense taken. I've had many 4WD vehicles before. However, I haven't had a new one in a while and I've never had a new Jeep. I actually like my Gladiator so I'm very sensitive to how I treat it. My wife calls me an "automotive hypochondriac."

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