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2015 6.2 Trans stuck in 2nd or 3rd

6.6LTZ

By 6.6LTZ
in Troubleshooting & Recalls

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Colossus Senior Enthusiast

Colossus

Posted
Posted

The joy of trying to diagnose problems in modern day electronically controlled vehicles.

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6.6LTZ Enthusiast

6.6LTZ

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On day 7. Called them this morning and they are still waiting on the cable. Said it SHOULD be here today.

L86 All Terrain Senior Enthusiast

L86 All Terrain

Posted
Posted

I have killed my 2015's battery about 10 times over the last two winters because i dont drive the truck in the winter salt. Even being dead for weeks at -30c, it will still hold a charge for a month without starting it even with the anti rust gimmick. I have a hard time believing that peoples batteries are causing these issues, I have never put a battery through so much hell and I load tested this spring before using it again and it is fine. My 6L80e has some issues in a 2014 I have, but they sound different that yours, mine is slamming itself into 2nd gear while driving and locks itself in there until I clear the code. Does it in the same spot on my commute every time. Now I know why to stay away from the first MY of the new platforms.

Rkaroll953 Enthusiast

Rkaroll953

Posted
Posted

mine gets stuck in 3rd gear about 2 times a year. all the dealer does it reset the computer and it takes it. other than that i have no problems besides the horrible trans tuning shifting like hell. I want to tune it so bad but idk about my issues losing my warranty

6.6LTZ Enthusiast

6.6LTZ

Posted
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mine gets stuck in 3rd gear about 2 times a year. all the dealer does it reset the computer and it takes it. other than that i have no problems besides the horrible trans tuning shifting like hell. I want to tune it so bad but idk about my issues losing my warranty

 

I was literally fixing to pull the trigger on a tune based on the positive feedback for the 8 speed shifting. I can't do it for fear of something else going wrong.

 

1 more time and the truck is gone.

Rme2513 Enthusiast

Rme2513

Posted
Posted

They called me yesterday evening and said they were going to order a battery ground cable and try that.

Mine was a bad ground from the engine to the fram they just took it off and cleaned up where it bolted down to and retightened it
Rme2513 Enthusiast

Rme2513

Posted
Posted

interesting, i should check my negative cable and engine ground

i would check all not just a few
Colossus Senior Enthusiast

Colossus

Posted
Posted

more than one ground wire to frame, there are several from what I understand.

6.6LTZ Enthusiast

6.6LTZ

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It has been a solid week of no check engine light. Pulled the boat 2 times this weekend and everything went good.

 

I still hate the trans and the way it shifts though.

6.6LTZ Enthusiast

6.6LTZ

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I noticed the other day that I there was a shudder from 2-3 or 3-4. It literally feels like about a second of rumble strips on the highway.

 

So today it done it several times. I thought well, just maybe I'm hitting some spots on the road. Nope, wife definitely feels the same thing and it got worse today. It even does it cruising 55-60 in 8th. Thoughts?

 

I'm going to call Monday and make another appointment for Thursday, on my day off, to take it in. Meanwhile I will probably test drive a 2500.

6.6LTZ Enthusiast

6.6LTZ

Posted
  • Author
Posted

The tech was able to reproduce the shudder. They ordered a torque converter and will work on it next week.

6.6LTZ Enthusiast

6.6LTZ

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Finally! I don't have but about 15 miles on the new converter but man, this thing shifts so nice now.

 

I hope this one holds up.

HondaHawkGT Senior Enthusiast

HondaHawkGT

Posted
Posted

Back to this dead thread...

 

Dealership just called and said the battery caused all of this. Said a low voltage battery will cause the trans to go in a limp mode.

 

Anyone heard of this?

 

yep, my Range AFM Disabler drained my battery just enough to make the truck freak out. Transmission had a mind of its own and had a few different messages about stabillitrack on the display. Went away after charging the battery back up.

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