Auto trans won’t go above 6th gear

[ScottBeach]

If your gear ratio and tire size are set right. I use tazer to see settings i am unsure how to check with other tools. Likely your issue is the self learning part of the trans. Which is why I suggest a reflash of the transmission. But. That isn't something the tools like tazer do. Need a trip to a dealer or shop that has the tools to do fw updates on the trans

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[Zachanadandy]

I thought that but the Jeep performs just fine in 7th & 8th if put there manually. I can roll 70
going uphill in 7th at @ 2000 RPM. I think the ones mentioning shift points are on to something. I just need someone to help
me flash it. Thought that is what the Superchips was supposed to do when flashed to the 5.13 gears. I am pretty sure the updated tire size that I entered is purely for the speedo.

Uphill at 2000 rpms... with the 3.6L? It's supposed to downshift at that point. Stock chargers won't pull hills at 2k rpm. The 3.6L doesn't make any power that low. Does it shift under normal situations where even a stock overdrive would? Downhill are you seeing 8th? Expecting it to not downshift under increased load at 2k rpm just isn't realistic.

 

[KevinC]

I would venture to guess it the Superchips Flashcal. I would get JScan up and running and see where you are at before making another change. Also, definitely look at wheel sensor and replace if needed before making adjustments.

 

[Mr.Wilson]

I thought that but the Jeep performs just fine in 7th & 8th if put there manually. I can roll 70
going uphill in 7th at @ 2000 RPM. I think the ones mentioning shift points are on to something. I just need someone to help
me flash it. Thought that is what the Superchips was supposed to do when flashed to the 5.13 gears. I am pretty sure the updated tire size that I entered is purely for the speedo.

If I shift to 7th or 8th manually then yeah it’s there but if I shift back to automatic it’ll down shift right to 6th. I have a taser installed and have rebooted it many times thinking it wasn’t doing its job. Nothing changed.

 

[Mr.Wilson]

If your gear ratio and tire size are set right. I use tazer to see settings i am unsure how to check with other tools. Likely your issue is the self learning part of the trans. Which is why I suggest a reflash of the transmission. But. That isn't something the tools like tazer do. Need a trip to a dealer or shop that has the tools to do fw updates on the trans

I’d love a dealer to flash my transmission to reset my shift points with my 37’s. I asked my dealership and they had ZERO idea what I was talking about.

 

[ScottBeach]

I haven't asked but who else other than the dealer could flash the firmware ?

 

[Stan H]

So I am having a new issue with my 22 Sport Max tow. It has been re-geared to 5.13 with e-lockers, the housings are trussed, front gusseted, with Reid knuckles and Timken main unit bearing housings. Computer flashed with Superchips FlashCal for gears and tore size. This was all done a little over a year ago. I had been running 37’s and just upped to 40’s, with the tire size upgraded with the FlashCal again. Here is the issue. The engine revs abnormally high between shifts and it wont’t go a above 6th on the highway l, running @ 3200 RPM. If I shift it manually, it accelerates normally and will easily run 7th or 8th on the highway @ 2100rpm. Running on flat ground @ 70mph, in 8th gear, if I move it back to auto, it shifts down to 6th. It almost seems like the trans doesn’t know what speed the vehicle is going. The trans shifts fine when it does shift, and shifts smoothly in manual mode. There are no shudders/clunks or anything else that would make me think something internally is failing. I tried to reflash with the FlashCal again tonight and got an error that it could not authenticate the ABS system. Based on that, I am thinking in my wheeling adventures I may have a wheel sensor that has failed/is failing. No lights on the dash. Opinions please?

Okay so the first time I went bigger tores I entered manually 2 times .. no power , no auto shifts in 7th or 8th . So I let it do tire size wizard auto calibration did it on the highway . First set of tires it chose 33" I was wearing 34.5.(35's) and new tires Little taller than the first upgrades and it chose 33.25 and both times shifts perfect plenty of power and all gears.
My opinion it is a relearn issue.
I have the flash cal + and it did a wonderful job. Now alternatively a J scan can do a complete reset of the TCM . But the flash cal + was the ticket for me.

 

[Clark]

Good job

 

[Stan H]

I’d love a dealer to flash my transmission to reset my shift points with my 37’s. I asked my dealership and they had ZERO idea what I was talking about.

That is because in there star scan tool it is no longer available to them under the main amount they pay to use the software. As I understand it it may not even be offered to them as a tool anymore. One guy said it can be purchased as a seperate program by request for like 2,500.00 dollars . Hard to say you read so much stuff anymore. Regardless all my dealers said the same thing . So I went to Flash cal + and Whamo fixed the issue .

 

[Bjeepz]

I get the same behaviour with my Mojave on 37's, no reprogramming device to account for the larger tires. I have noticed the high revving and holding 4th/5th too long before shifting has become worse over time and also the shifting to 7th and 8th. Cold weather seems to make it worse which seems like possible coincidence. I can drive the same short section of hwy where we have pretty low speed limits of 80kmh/50mph, of course not uncommon to go 10-20kmh over where there are no speed cameras, I get varying results daily. When I manually shift all works perfectly, often manually shift from 6th to 7th and see fuel consumption reading drop a litre or two per 100km. Not sure where to go with this!

 

[Stan H]

I get the same behaviour with my Mojave on 37's, no reprogramming device to account for the larger tires. I have noticed the high revving and holding 4th/5th too long before shifting has become worse over time and also the shifting to 7th and 8th. Cold weather seems to make it worse which seems like possible coincidence. I can drive the same short section of hwy where we have pretty low speed limits of 80kmh/50mph, of course not uncommon to go 10-20kmh over where there are no speed cameras, I get varying results daily. When I manually shift all works perfectly, often manually shift from 6th to 7th and see fuel consumption reading drop a litre or two per 100km. Not sure where to go with this!

You definitely sound like you need to recalibrate your tire size in the computer. Tazer or Flash-cal + they do NOT mess with any environmental issues. All they will donis allow the tire size to be updated . Takes just a few min. Best $185.00 I ever spent !!

 

[Bjeepz]

You definitely sound like you need to recalibrate your tire size in the computer. Tazer or Flash-cal + they do NOT mess with any environmental issues. All they will donis allow the tire size to be updated . Takes just a few min. Best $185.00 I ever spent !!

Ya I had planed to buy the ECRI device as it does all I am looking for. However based on some info in this thread seems ppl who have recalibrated are experiencing the same issue.

 

[Sticks702]

I haven't asked but who else other than the dealer could flash the firmware ?

I have the same question. No way I can take the Jeep with 40’s on it to the dealer for anything.

 

[Sticks702]

You definitely sound like you need to recalibrate your tire size in the computer. Tazer or Flash-cal + they do NOT mess with any environmental issues. All they will donis allow the tire size to be updated . Takes just a few min. Best $185.00 I ever spent !!

I have already reset tire size and gear ratio with the FlashCal.

 

[Bjeepz]

Any progress with this Sticks702 ?

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