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do these automatically idle up/accelerate in 4 low to climb over obstacles?

MoxiesDad

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I put my front end up on ramps esterday using 4 low to slowly climb up. I'm pretty sure the engine idled up on it's own to climb it. Do they do this? It was my first time using 4 low.
I noticed the same thing with my 2021 JT Rubicon the first time I put it in 4L with offroad+ on. Just idled around, feet off the pedals, came up to a small rock, momentarily slowed then sounded like engine got more throttle and pulled right over the rock. I wasn't using the offroad cruise control. Totally different than my 2004 TJ Rubicon where you have to give it some gas to go over any obstacle.
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I noticed the same thing with my 2021 JT Rubicon the first time I put it in 4L with offroad+ on. Just idled around, feet off the pedals, came up to a small rock, momentarily slowed then sounded like engine got more throttle and pulled right over the rock. I wasn't using the offroad cruise control. Totally different than my 2004 TJ Rubicon where you have to give it some gas to go over any obstacle.
exactly! Almost exactly the same experience as you but I compared it to my 2006 TJ. I swear I heard the engine accelerate on its own.
 

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Think about how dangerous it would be if it, on its own, all by itself, suddenly idled up and over something if duck mode wasn't being used. Other car companies have been sued over "unexpected acceleration".
 
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Think about how dangerous it would be if it, on its own, all by itself, suddenly idled up and over something if duck mode wasn't being used. Other car companies have been sued over "unexpected acceleration".
well I know what I heard/experienced. It definitely idled up. I’ll do it again and record it.
 

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well I know what I heard/experienced. It definitely idled up. I’ll do it again and record it.
Normal warm idle speed - engine warmed up, about 800 RPM give or take. So in your experience, it, in gear, exceeded 800 RPM..........it didn't drop to say, 500 or 600, and then recover to 800 RPM.
That should be cause for concern, not a "hey, that's cool" thing. It could mean when approaching an obstacle, rock, branch, whatever, and you let up to make a decision, it could, on its own, accelerate over that obstacle.

Watch the tach - check out the idle speed in gear and see if it increases over 800 RPM and get a video of that while your foot is off the gas and it's not in duck mode but simply in 4L and nothing else is turned on or engaged.
 

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Watch the tach - check out the idle speed in gear and see if it increases over 800 RPM and get a video of that while your foot is off the gas and it's not in duck mode but simply in 4L and nothing else is turned on or engaged.
I didn’t see the tach so I’ll definitely pay attention to that. Was planning to do everything you just said but I just came up with a better idea to use the Torque app to show all that plus commanded idle speed and throttle input (if the PID for that is available). It’ll have to be tomorrow though because I’m STILL at work.
 

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I didn’t see the tach so I’ll definitely pay attention to that. Was planning to do everything you just said but I just came up with a better idea to use the Torque app to show all that plus commanded idle speed and throttle input (if the PID for that is available). It’ll have to be tomorrow though because I’m STILL at work.
Yeah, any good app will show the percentage of throttle and so on.
 

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That i knew. My question was if the engine is supposed to speed up, wihtout me pressing the pedal, to crawl up/over obstacles on it's own. I'm almost certain i heard it do this yesterday. I didn't see anything in the manual that says it would do this which is why i asked.
It’s hill climb assist I’m fairly sure. It’s selectable in the menus.
 

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well I know what I heard/experienced. It definitely idled up. I’ll do it again and record it.
You’re not wrong. But it does it after a pause. It takes a second or two after removing your foot from the brake.
 

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Normal warm idle speed - engine warmed up, about 800 RPM give or take. So in your experience, it, in gear, exceeded 800 RPM..........it didn't drop to say, 500 or 600, and then recover to 800 RPM.
That should be cause for concern, not a "hey, that's cool" thing. It could mean when approaching an obstacle, rock, branch, whatever, and you let up to make a decision, it could, on its own, accelerate over that obstacle.

Watch the tach - check out the idle speed in gear and see if it increases over 800 RPM and get a video of that while your foot is off the gas and it's not in duck mode but simply in 4L and nothing else is turned on or engaged.
It’s a rock crawling feature. I promise it’s not dangerous. It doesn’t do anything weird or scary. It’s an automatic transmission with hill climb assist turned on, in drive, with the foot off the brake.
 

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It’s a rock crawling feature. I promise it’s not dangerous. It doesn’t do anything weird or scary. It’s an automatic transmission with hill climb assist turned on, in drive, with the foot off the brake.
He's talking of just being in 4L not any other mode, not duck mode, no assist. ONLY 4L.
 

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He's talking of just being in 4L not any other mode, not suck mode, no assist. ONLY 4L.
I’m aware. Hill start assist is not the same as duck mode. And it’s defaulted to be turned on.
 

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I’m aware. Hill start assist is not the same as duck mode. And it’s defaulted to be turned on.
Hill start assist uses brakes to hold position when you take off going up a hill. Take foot off brake and it holds position by braking gently
 

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BRAKES, not throttle. Only "duck mode" or speed control for hill descent uses throttle - down hill and only when you press the button.

Jeep Gladiator do these automatically idle up/accelerate in 4 low to climb over obstacles? 1686407198032

Jeep Gladiator do these automatically idle up/accelerate in 4 low to climb over obstacles? 1686407272838

Jeep Gladiator do these automatically idle up/accelerate in 4 low to climb over obstacles? 1686407247383


Hill Start Assist can be enabled or disabled in the menus in the radio.
If it's enabled, it works any time the above is true.
If it's disabled, it won't ever work.
Hill Start Assist never uses engine speed or throttle.
It's a godsend on a fair hill with a stick - you are sitting in heavy traffic, the light turns, you take your foot off the brake and touch the throttle while letting up on the clutch to take off - and the vehicle rolls backward 6" into the car behind you. This mitigates that by holding the brake for you while you operate throttle and clutch.
And even with automatics, the idle speed is not sufficiently high enough to hold position with foot off the brake, so it helps there, too.

(Sure wish my 73 with a 2400 stall converter had this feature! There's zero drag until you rev the engine over 2,000 RPM so it rolls really super easy in gear.)

Using throttle for such things - especially when unexpected, is, yes, risky, even dangerous. It applies throttle but how would it react if it went over the top of the ramps?
Sorry, if you have it in gear, 4L and it uses throttle, it is indeed risky. Only the driver knows exactly when to stop forward motion.

Even "duck mode" you must have the seat belt fastened for it to work -

Jeep Gladiator do these automatically idle up/accelerate in 4 low to climb over obstacles? 1686407889368

Jeep Gladiator do these automatically idle up/accelerate in 4 low to climb over obstacles? 1686407931851

Jeep Gladiator do these automatically idle up/accelerate in 4 low to climb over obstacles? 1686407964478


So doors must be closed, driver seat belt buckled.

If the door is open and/or the seat belt not connected, then even this won't function.
I doubt the seat belt was on driving up ramps.
I never buckle up for driving up ramps or connecting to a snow plow or trailer.

So it wasn't hill start assist and it wasn't SSC or duck mode.
 

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Hill start assist uses brakes to hold position when you take off going up a hill. Take foot off brake and it holds position by braking gently
That’s brake hold.
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