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8 speed trans shudder 1500-2200 1-3 gear

Bigmac

By Bigmac
in Engines & Drivetrain

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Bigmac Enthusiast

Bigmac

Posted
Posted

So my 2nd new truck n 2 years. Had a 5.3 2015 LTZ. Worked great but wanted something stronger to pull a larger rv. Found exactly what I wanted on a lot. 2017 GMC 6.2 8 spd max tow DC. Have driven it 2000 miles and love it. It was built in January 2017 so I figured any trans problems would have been worked out. Drives

and shifts so much better than my 2015 I was happier than a gopher in soft dirt ? So it has stated to shudder in mostly low rpm1500-2200 and 2-3 gear worse pulling slight grade from a dead stop. No rv or anything. Thinking it is a torque converter problem but looking like a dealer visit is in order. Towing my light trailer is not an option as I just towed it home and it really shakes. Get above that rpm range and all is good. Freeway driving is great. No shake or shudder. Guess I was bragging to much on how good it was. Any thought s holler.

Justin101714 Enthusiast

Justin101714

Posted
Posted

I've repaired many of these 8 speed transmission concerns. I would suggest your dealership follow this bulletin. #16-NA-175. They'll know what that is. They need to drive the vehicle while commanding the TCC (torque convert clutch) on and off while the concern happens. If they are able to stop the shudder when commanding the TCC with the scan tool, then you'll need a torque converter and new fluid.

 

 

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Bigmac Enthusiast

Bigmac

Posted
  • Author
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Thanks Justin I waited to buy a mid year build to hope all trans problems where worked out.

Justin101714 Enthusiast

Justin101714

Posted
Posted

Thanks Justin I waited to buy a mid year build to hope all trans problems where worked out.

There's also a flush procedure they need to perform first before replacing any parts. It involves flushing the complete trans fluid three times and changing the filter, then re-evaluating the concern. This fixes some of them too. What's happening with these 8 speeds is the clutch material is wearing in and getting stuck in the torque converter causing an imbalance and there's no way to get it out when it gets bad enough, the flush saves some of them, not all.

 

 

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Lgetz Senior Enthusiast

Lgetz

Posted
Posted

I had my torque converter replaced and was fine for 4K miles. Began noticing light shudder again and this time they did a flush and refilled with synthetic fluid. Now at 1K miles it has been good.

Bigmac Enthusiast

Bigmac

Posted
  • Author
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Made appt at local dealer. First words out of his mouth - never heard of that problem. that's some good factory training right there. I worked the auto repair business all my life so I chuckled when I heard that

SkiDooNick700 Enthusiast

SkiDooNick700

Posted
Posted

I'll have to follow this story. Im thinkin next time I'm at the dealer i want to set up a ride along with a tech to see if my trans is really acting weird or not. Some days it's really clunky and other days its really smooth.

Bigmac Enthusiast

Bigmac

Posted
  • Author
Posted

No problem with my shifts. Most are butter smooth. Just chasing the vibration shudder feeling on low roms. Tech to ride with me for duplication.

Bigmac Enthusiast

Bigmac

Posted
  • Author
Posted

New converter ordered. Now - the rest of the story. To be continued when it's replaced

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