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Discussion Starter · #1 ·
I'm just wondering if anyone has experience with either of these TCM flashes. I have a 2015 with 35s and just upgraded to 4.88 gears. Now it holds the gears too long. The Jeep has been programmed for the tires and gears. The speedometer is correct. I'm looking into having the TCM reprogrammed. So far these are the only two I have found that offer this service. I'd really appreciate some feedback from people who have used these or anything else that actually reprograms the TCM shift points, not just something like a Flashcal or Procal. Thanks
 

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i use the superchips F5 on my jeep after I regeared and it worked great.
 

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I feel the same as you my Jeep tends to hold too long before shifting. If I let off the gas and get back on it it will shift. No experience with changes to the TCM though.


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I have a Flashcal F5 and it did nothing to help with the Jeep holding each gear for way too long. It especially does not want to shift when going up hills.
thats odd I dont have that same issue.
 

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I have the one through OST Dyno. Pretty simple swap. I've had a random issue with a faulty TCM throwing sporadic "Hot Oil" codes, but it fixed the shift point problems (lift to shift and revving way too high). A new one was sent to me with no problems. They have had good customer service. They will work with you on getting the shift points right where you want them, but keep in mind you will have to send your TCM in everytime you want a change.

For what it is worth, I've heard nothing good or bad about RPM Extreme.
 
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Discussion Starter · #7 ·
I have the one through OST Dyno. Pretty simple swap. I've had a random issue with a faulty TCM throwing sporadic "Hot Oil" codes, but it fixed the shift point problems (lift to shift and revving way too high). A new one was sent to me with no problems. They have had good customer service. They will work with you on getting the shift points right where you want them, but keep in mind you will have to send your TCM in everytime you want a change.

For what it is worth, I've heard nothing good or bad about RPM Extreme.
I really appreciate your response. What options did they give you for changing your shift points? Did they ask for your input at all? I also read about them mentioning something about changing the shift firmness. Have you noticed any difference with that? I'm really thankful for any information you can provide as I am wanting to have this done soon, I just can't really find any information on it.
 

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Why not a simple and inexpensive, yet uber reliable fix - Jscan?

Available for both iOS and Android. Allows you to change tire size and gearing which changes the shift points in automatic transmissions. Great customer service as well. Buy an ODB II and a license for Jscan for about $60 all in. You can download the free version to see what features are available and if it fits what you are looking to do?

JScan ? OBD JScan ? Mobile Jeep Diagnostic Tool
 

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Discussion Starter · #9 ·
Why not a simple and inexpensive, yet uber reliable fix - Jscan?

Available for both iOS and Android. Allows you to change tire size and gearing which changes the shift points in automatic transmissions. Great customer service as well. Buy an ODB II and a license for Jscan for about $60 all in. You can download the free version to see what features are available and if it fits what you are looking to do?

JScan ? OBD JScan ? Mobile Jeep Diagnostic Tool
Actually, I already have that. I used it to turn off my swaybar light. It does not help this issue. That's why I'm asking for people that actually have experience with a reprogrammed TCM, not people who have just recalibrated for larger tires and different gears using a Flashcal, Procal, or Jscan.
 

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I really appreciate your response. What options did they give you for changing your shift points? Did they ask for your input at all? I also read about them mentioning something about changing the shift firmness. Have you noticed any difference with that? I'm really thankful for any information you can provide as I am wanting to have this done soon, I just can't really find any information on it.
I honestly can't speak on shift firmness as I don't really remember what it felt like before. As far as options on the shift points, they have 2 different stock tunes: Highway and Mountain (I think that is what they are called). Highway is basically just an economy TCM tune. It puts your shift points at a very reasonable RPM for smooth cruising. The mountain tune (what I went with, but I'm not sure I wouldn't go for the lighter one if I did it again-IDK) puts the shift points a little higher (about 3200 RPM) while applying normal (30ish %) throttle while accelerating. Those are just starting points though. If you prefer shifting earlier or later, I haven't had any issue with them when sending it in for adjustments. They will work to get it right for you (at least in my experience so far).
 

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Actually, I already have that. I used it to turn off my swaybar light. It does not help this issue. That's why I'm asking for people that actually have experience with a reprogrammed TCM, not people who have just recalibrated for larger tires and different gears using a Flashcal, Procal, or Jscan.
This is exactly what I was dealing with before I got mine. I was using a Flashcal, and while it corrected my Speedo and allowed for the lower gearing, it didn't fix my shift point issues. There are quite a few Jeepers out there that have this issue. In fact, you actually have to have a programmer of some sort even with the new TCM to reprogram it to your gear ratio and tire size.
 

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Discussion Starter · #12 ·
[/quote]I honestly can't speak on shift firmness as I don't really remember what it felt like before. As far as options on the shift points, they have 2 different stock tunes: Highway and Mountain (I think that is what they are called). Highway is basically just an economy TCM tune. It puts your shift points at a very reasonable RPM for smooth cruising. The mountain tune (what I went with, but I'm not sure I wouldn't go for the lighter one if I did it again-IDK) puts the shift points a little higher (about 3200 RPM) while applying normal (30ish %) throttle while accelerating. Those are just starting points though. If you prefer shifting earlier or later, I haven't had any issue with them when sending it in for adjustments. They will work to get it right for you (at least in my experience so far).[/QUOTE]

Thank you for providing actual experience with this. I think I’ll go with the Highway/Economy tune. I think people saying they don’t have an issue with the stock TCM tune after a regear, either live somewhere extremely flat, or didn’t pay much attention to how their vehicle previously drove to notice it changed.
 

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I run the OST TCM in my daughters after the dealer decided to do a transmission update flash during a routine oil change with her superchips loaded for tire and gear change. It would not up-shift until you let off the gas. The OST TCM fixed the issue. It took 2 try's to get it to shift similar to the wife's Rubicon but Mike was very easy to work with and made the adjustments quickly.
 

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Discussion Starter · #15 ·
I run the OST TCM in my daughters after the dealer decided to do a transmission update flash during a routine oil change with her superchips loaded for tire and gear change. It would not up-shift until you let off the gas. The OST TCM fixed the issue. It took 2 try's to get it to shift similar to the wife's Rubicon but Mike was very easy to work with and made the adjustments quickly.
I just received my new TCM from OST. It helped a ton with how it shifts. What all did you ask them to change from their standard tune?
 

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Good info.
Actually, I was thinking of taking a road trip out there one day.
My '12 has never shifted right, since new.
Figure if I drive out there and let them do it, and try it before leaving, it will avoid sending it back and forth three or four times.
 

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He usually is at Bantam Jeep Fest from what the guy who introduced him to me said. His shop is not too far away from there.
 

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Discussion Starter · #20 ·
I've had the OSTdyno TCM for about a month now. Thank you so much to the people that provided their experience with this tune. It made this process so much easier. It's really hard to believe how much this new TCM makes the Jeep more enjoyable to drive. If anyone is reading this and on the fence about making this purchase, just do it. You won't believe how much better your Jeep will drive.
 
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