2016 JKU Automatic Transmission ?

RUBINOT

RUBINOT

Caught the Bug
I have a 16 JKU with a Auto tranny, 2500 miles. The JKU is lifted, running 35" tires, 4:56 gears and a rearE-Locker. The computer has been adjusted with a Procal unit for the tires and gears. The JKU drivers perfect on the roads at home.

This is my first Jeep with a Auto Tranny so I'm learning the quirks of it.

My son is currently in Estes Park Co. on his Honey Moon with my jeep. He called me and stated that while on Fall River Rd, a very easy dirt road, he noticed the rpms were higher before the tranny shifted. He stated it shifted normal in town, but as they drove up this road to the top of the mountain that's when noticed the rpms were higher for shifting. He said it was slow driving, biy extremely easy road.

He stated as a precaution, he used the bump shift which worked fine while on this road.

Is this normal for a auto tranny at higher elevations and slow driving to shift at higher rpms.

We will be meeting up with them in Frisco Co. this weekend for our family vacation, getting my jeep back and lots of wheeling.
 
My auto does the same thing. 2015 two door 2.5 inch lift and 33s. Does a slipping thing sometimes. I've read it's normal and just what they do. I just had my transmission reprogrammed at the dealership and it still does it. Especially going up a steep grade when I put my foot in it. Think it's a normal thing.
 
Simple. The automatic transmission has a level on it. So when you are on unlevel ground, it will shift differently. In his case, it will keep the RPM's higher so to keep the engine workload low during uphill climbing. Otherwise, it would constantly hunt for the right gear.
 
Rubinot I have a 2015 JKUR with the auto and the first couple of months it definitely took a little getting use to. I am also in Colorado and like you mentioned on longer hills you would feel the transmission hold the gear longer. It is definitely nice when you are heading up I-70 or some of the mountain passes to not have it jumping gears like my '11 JKU sport did. I dont really notice it anymore so I think I just got use to it.
 
I hate it when it does it. Ruins mpg and tends to get damn near overheating levels due to it. I so wish I could change when and where it shifts.
 
There is an option on the '12 and up JK (including the '15 and '16) to program the shift points of the auto trans. A place in PA called OST Dyno will program the TCM for the tire size you run, and alter the shift points to be more manageable (not so high). If you don't like the initial program, you get 3 updates at no extra charge, to fine tune the TCM programming. Some negatives are that it's no cheap (around $400 minimum), it requires you to remove your TCM and send it to them which leaves your Jeep undriveable in the mean time, and during any TCM program revisions that you want done later. To avoid the down time, you can buy a 2nd TCM from them for $250, which raises the cost even more to almost $650 total. I haven't done it yet, and I'm not sure if I dislike the auto trans shift points enough yet to spend that kind of money to attempt to have it fixed. There are only like one or two reviews from Jeep JK owners on their TCM, but it seems like the Challenger/ChargerGrand Cherokee SRT people have used them for PCM/TCM tuning with good results.
 
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highoctane said:
There is an option on the '12 and up JK (including the '15 and '16) to program the shift points of the auto trans. A place in PA called OST Dyno will program the TCM for the tire size you run, and alter the shift points to be more manageable (not so high). If you don't like the initial program, you get 3 updates at no extra charge, to fine tune the TCM programming. Some negatives are that it's no cheap (around $400 minimum), it requires you to remove your TCM and send it to them which leaves your Jeep undriveable in the mean time, and during any TCM program revisions that you want done later. To avoid the down time, you can buy a 2nd TCM from them for $250, which raises the cost even more to almost $650 total. I haven't done it yet, and I'm not sure if I dislike the auto trans shift points enough yet to spend that kind of money to attempt to have it fixed. There are only like one or two reviews from Jeep JK owners on their TCM, but it seems like the Challenger/ChargerGrand Cherokee SRT people have used them for PCM/TCM tuning with good results.
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Why not just buy a SuperChips TrailDash 2 for 500? Much more capability there.
 
caminton said:
Why not just buy a SuperChips TrailDash 2 for 500? Much more capability there.
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Last I looked into it the Traildash 2 only adjusts PCM programming items like fueling trim and timing, and do nothing on the TCM. This also applied to the tuners from ALL the major companies out there. None of them allow you to change transmission shift points or alter TCM programming. Also, it won't work on a '15 or newer JK at all because the PCMs are locked, and the encryption has not been cracked yet by any of the tuning companies out there. To tune the PCM on a '15 or newer JK you have to buy a new PCM from somebody like Diablosport for a '14 JK, which is $600 alone without any tuning at all. I could be wrong though, did something recently changed and tuners like Superchips, Diablosport, etc are now able to tune shift points on '12 and up JKs?
 
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Thanks for the input, kinda what I was figuring but want to double check, since I'm a newbie to the Automatic, hahahaha

I'll be putting ot to the trst starting Saturday on trails near Frisco/Breckenridge Colorado and there are a ton of them :)
 
This makes me very upset when I'm driving up I-70. It will hold the higher RPMs for what seems like a very long time. I end up just using the tap shifter and click it to the right to grab a gear.

Going up the steep hills on the highway makes me want a manual back.
 
It's reassuring to hear other 2015 owners are experiencing the same thing. I moved to CO from CA earlier this year and immediately noticed the higher RPM's and longer shift points. I took my Jeep into the dealer and got the new Software update for the auto transmission thinking it might help. I did not notice any difference. The tech working on my Jeep said its functioning completely normally, its just the result of high altitude and big tires.

No biggie, if I wanted to go fast I would have bought a sports car ;)
 
nautie said:
It's reassuring to hear other 2015 owners are experiencing the same thing. I moved to CO from CA earlier this year and immediately noticed the higher RPM's and longer shift points. I took my Jeep into the dealer and got the new Software update for the auto transmission thinking it might help. I did not notice any difference. The tech working on my Jeep said its functioning completely normally, its just the result of high altitude and big tires.

No biggie, if I wanted to go fast I would have bought a sports car ;)
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Honestly the WA580 shift points are shit no matter how you spin it. I've tried multiple different tire size settings in my programmer. It still likes to upshift while I'm slowing down then bog out. Really annoying.

Sent from my ONEPLUS A3000 using WAYALIFE mobile app
 
H8ROADS said:
I hate it when it does it. Ruins mpg and tends to get damn near overheating levels due to it. I so wish I could change when and where it shifts.
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I simply go into auto shift mode to manually choose shift points and rpm...it's what I like about the NAG1
 
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