How often should I engage the Part Time 4x4 systems?

CBH

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I pinged Jeep recently asking them “if I drive in 4H Auto, the default system on my 392, and never engage the Part Time 4L or 4H Systems, will I damage the Part Time Systems due to neglect?”

The reason I asked: I didn’t see anything in the manual recommending engaging the Part Time Systems occasionally to ensure those parts stay lubricated -- seems logical, right? I just wanted to know Jeep’s recommendation because I believe there are plenty of Jeep owners who use their Jeeps mostly on city streets and may not engage the Part Time Systems until neccessary.

The person handling my “case” reached out to a “Corporate Resource” who responded with the following:

"Driving in 4 wheel auto in 4 x 4 applications will not harm the other gears as the transfer case is a lubricated system and all components are lubricated at all times. If he is using this during regular street driving on dry pavement that could damage his system."

Anybody understand what “Corporate” is saying?
 
Translation: "Leave the vehicle drive system exactly as it was as you purchased it. Any movement from the original position could damage said drive system..."


Seriously - I have no idea why they dance around it. Do they really think 392 owners all know nothing about proper engaging of part-time 4WD systems (since that is essentially what you're doing when you go 4H ot 4L from 4A) I'm in total agreement with you @CBH - the AWD system behaves differently than a true 50/50 split of 4WD. It needs to be enaged to "stretch its legs" every now and then. Keep the 'ole muscles loose and greased up.
 
Translation: "Leave the vehicle drive system exactly as it was as you purchased it. Any movement from the original position could damage said drive system..."


Seriously - I have no idea why they dance around it. Do they really think 392 owners all know nothing about proper engaging of part-time 4WD systems (since that is essentially what you're doing when you go 4H ot 4L from 4A) I'm in total agreement with you @CBH - the AWD system behaves differently than a true 50/50 split of 4WD. It needs to be enaged to "stretch its legs" every now and then. Keep the 'ole muscles loose and greased up.
So, I responded to Jeep with:

"Is your "corporate resource" telling me that driving in 4H Auto in "regular street driving on dry pavement" could damage the 4 x 4 system?"

Their answer was, “That is correct."

So, in essence, according to "Jeep Corporate”, driving my 392 in the default 4H Auto mode is damaging the 4x4 System. Hmmm....
 
So, I responded to Jeep with:

"Is your "corporate resource" telling me that driving in 4H Auto in "regular street driving on dry pavement" could damage the 4 x 4 system?"

Their answer was, “That is correct."

So, in essence, according to "Jeep Corporate”, driving my 392 in the default 4H Auto mode is damaging the 4x4 System. Hmmm....
Dipshits! If you look at one version of the 392 performance supplement it does say exactly that.
 
Dipshits! If you look at one version of the 392 performance supplement it does say exactly that.
I guess the Jeep guy handling my query is just reading from the “script”; in this case a poorly worded supplement. I learned in a previous life before you issue any technical guidance you need to step back and ask yourself (and the engineers waiting for you to sign off on it), “does this make sense?” In some cases I had to say, “show me.”
 
I pinged Jeep recently asking them “if I drive in 4H Auto, the default system on my 392, and never engage the Part Time 4L or 4H Systems, will I damage the Part Time Systems due to neglect?”

The reason I asked: I didn’t see anything in the manual recommending engaging the Part Time Systems occasionally to ensure those parts stay lubricated -- seems logical, right? I just wanted to know Jeep’s recommendation because I believe there are plenty of Jeep owners who use their Jeeps mostly on city streets and may not engage the Part Time Systems until neccessary.

The person handling my “case” reached out to a “Corporate Resource” who responded with the following:

"Driving in 4 wheel auto in 4 x 4 applications will not harm the other gears as the transfer case is a lubricated system and all components are lubricated at all times. If he is using this during regular street driving on dry pavement that could damage his system."

Anybody understand what “Corporate” is saying?
Looks to me that they misunderstood your question. It’s like they thought you were asking, “Am I hurting my Jeep because its always in Full Time 4H (4H auto)?”

When they referred to using 4H auto in 4x4 applications, I believe they meant 4H part time.
 
Looks to me that they misunderstood your question. It’s like they thought you were asking, “Am I hurting my Jeep because its always in Full Time 4H (4H auto)?”

When they referred to using 4H auto in 4x4 applications, I believe they meant 4H part time.
You’re probably right. The guy I’ve been corresponding with admitted he knows ZERO about 4x4 systems; but that’s the world we live in now -- customer service reps who are just there to channel queries without any knowledge of the product.
 
Wrong! From the 392 supplement:


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Written by people that don't know how 4wd works. These are the same people that deny your warranty issues lol.
 
My 6yr old F250 has seen fewer miles in 4WD than the 392 saw in its first week. I find a spot to engage the four-wheel-drive system on the truck about once a quarter to ensure all the actuators are working and lubricated.
 
My 6yr old F250 has seen fewer miles in 4WD than the 392 saw in its first week. I find a spot to engage the four-wheel-drive system on the truck about once a quarter to ensure all the actuators are working and lubricated.
I live on a barrier island (11 feet above sea level) with no place to off road; fortunately there are dirt roads/paths alongside the causeways where I can briefly “exercise” the part time systems. That should work.
 
I think the biggest issue is the use of 4H AUTO term incorrectly - consistently - by Jeep! The 4 H AUTO is essentially the 392's AWD mode. Where they keep screwing up is the verbiage SHOULD be "The 4H PART TIME and 4L are intended for low-traction situations... the "auto" IS intended for everyday driving... unless Jeep decided to switch around 40 year old terminology on us and I have it completely bass ackwards.



(Or just update the dang manual to say "Don't lock the front on dry pavement" period)
 
Looking at the Wrangler 392 Performance Features Guide


It seems to me the correct language is used

4H AUTO
Four-Wheel Drive Auto High Range — This range is for normal street and highway driving on dry, hard surfaced roads. This range sends power to the front wheels. The four-wheel drive system will be automatically engaged when the vehicle senses a loss of traction. Additional traction for varying road conditions.
4H PART TIME
Four-Wheel Drive Part Time High Range — This range maximizes torque to the front driveshaft, forcing the front and rear wheels to rotate at the same speed. This range provides additional traction for loose, slippery road surfaces only.
 
In one of the online versions I have read the introductory part was correct but then later slipped into typo category lumping 4 Auto and 4 Low into the same, off road only, category.
 
In one of the online versions I have read the introductory part was correct but then later slipped into typo category lumping 4 Auto and 4 Low into the same, off road only, category.
Unfortunately, after all of the correspondence from Jeep, they still haven’t answered my original question regarding how often, if at all, should I engage the Part Time Systems, given I will drive primarily in 4H Auto. The answer may be “it’s not necessary because all of the components are lubricated while in 4H Auto” or it could be some frequency like monthly, quarterly, annually, etc.
 
Unfortunately, after all of the correspondence from Jeep, they still haven’t answered my original question regarding how often, if at all, should I engage the Part Time Systems, given I will drive primarily in 4H Auto. The answer may be “it’s not necessary because all of the components are lubricated while in 4H Auto” or it could be some frequency like monthly, quarterly, annually, etc.
I think if they really wanted a timed interval they would state that in the owners manual. My Jeep gets put into 4 Hi/Low about every week but my truck maybe once a year. Not a problem with either one. If you have the chance on a dirt road just engage 4 HI/LOW when you can. Getting into 4lo in some transfer cases takes a slight bit of finesse and just a little forward motion so getting used to it is a good idea.
 
I think if they really wanted a timed interval they would state that in the owners manual. My Jeep gets put into 4 Hi/Low about every week but my truck maybe once a year. Not a problem with either one. If you have the chance on a dirt road just engage 4 HI/LOW when you can. Getting into 4lo in some transfer cases takes a slight bit of finesse and just a little forward motion so getting used to it is a good idea.
I’ve done it twice since June on the dirt road alongside one of the causeways. It worked well. This is my 4th Jeep; but the first one with 4H Auto.
 
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