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2020 Sierra SLT Shudder

Evan Whatley
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SSsierra Enthusiast

SSsierra

Posted
Posted
On 1/13/2021 at 11:21 AM, hotrodz37 said:

 

I wound up pulling my 2 deg pinion shims that came from the factory and my issue is completely gone. My truck was at the dealer for a week them thinking it was a trans issue and then came back with "operating as designed". I ordered a digital angle finder from amazon and got to work. My operating angle was way off - no idea why my truck had shims from the factory and in the wrong direction mind you. It was quite a hassle to get them out but once I did I couldn't be happier. Measured angles afterward and everything is in spec now. Unreal GM, Unreal. 

Good to hear you got it resolved, I wish I could remove the shims and be done with it but yesterday I got under my truck to check for shims and there isn’t any shims nor did I see a factory block in rear

carnau Enthusiast

carnau

Posted
Posted
On 1/19/2021 at 6:58 PM, Megalomegalodon said:

According to the article MQE replaced M5U but was a revised transmission with changes. Probably didn't fix the issue but I have not yet had it happen to me.

 

Snippet from article - https://gmauthority.com/blog/2019/06/the-gm-8-speed-transmission-just-needs-to-go-away-asap/

 

"Following a litany of complaints, GM tried to “improve” the 8-speed in the 2019 Silverado and 2019 Sierra. In a press release, the automaker said it made “enhancements designed to improve shift quality, while also adding a new centrifugal pendulum absorber torque converter” to improve smoothness. The new revised transmission was assigned RPO code MQE, replacing the M5U 8-speed unit on the half-ton Silverado and Sierra, but not (yet) on other GM products like full-size SUVs or mid-size pickups."

That's right. The MQE replaced the M5U. The MQE is what comes in all 19/20 trucks though. So the guy in this thread would have the MQE transmission as well. 

That's all I was saying.

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