What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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Joseph Garcia

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I got my truck back today from my local tuner, who was working on eliminating a very hard downshift from 5th gear to 4th gear. He told me that he did his best, but he could not fully eliminate the hard downshift. Even though it is a newly rebuilt 6180 transmission, he believes that the root cause of the issue is something electrical, mechanical, or both inside the transmission. He gave me a referral to a local transmission specialist who would be willing to tear into the transmission to try to find the root cause of this issue. So, I will be reaching out to him in the near future.

@NickTransmissions, is there anything that comes to your mind regarding a hard downshift issue that occurs only when the transmission tries to downshift from 5th gear to 4th gear?
 

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