Two problems related to automatic transmission control module have been reported for the 2020 Chevrolet Silverado 3500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2020 Chevrolet Silverado 3500 based on all problems reported for the 2020 Silverado 3500.
VIN: [xxx] make/model/year: 2020 Chevrolet Silverado 3500hd, duramax l5p, allison 10l1000 recall: n242454440 / n242454441 (NHTSA 24v797) description: vehicle had n242454440 completed may 2026 (tcm software update for harsh shift / wheel lockup). On xxx at 103k miles, vehicle exhibited same defect: harsh downshift 8th-9th gear, cel on. Diagnosed as tcm failure per n242454441. Vehicle at o'reilly Chevrolet tucson since xxx (18 days out of service as of xxx). Dealer states tcm on national backorder, spac ticket opened, no eta. Dealer denied courtesy transportation stating out of warranty at 103k, despite recall being federal safety recall with 15yr/150k special coverage. This is failure of remedy for safety recall that can cause momentary rear wheel lockup. No parts available, no transportation provided. What I want: gm to provide rental coverage and expedite tcm repair per recall obligations. Owner: [xxx], [xxx], [xxx], [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).
The sudden rear wheel lock up recall that gm has released for the 2020+ silverado's with the 10-speed transmission does not go far enough. The recall simply reprograms the pcm to alert the driver 10,000 miles prior to the valve in the valve body failing, puts the vehicle into limp mode, and extended the warranty on the valve body to 15 years or 150,000 miles. Gm states there is no fix available and this is not correct. Nextgen drivetrain has developed a fix for this per their website [xxx] ). On their site they also provide videos of trucks experiencing the lock up where it seems that the vehicle downshifts to 2-nd gear at high speeds and creates a violent jolt. This is extremely troubling to me as these vehicles are meant to tow, and I am very fearful that this issue will happen while towing a long trailer while my family and I are traveling and putting them in danger of an accident. It is very concerning to me that NHTSA would allow for this type of a "fix". I am not sure if you have seen the videos of this issue happening, or know that a fix does seem to have been developed. I ask that you please reopen this investigation and revisit the way gm is handling this recall, and look into the fix that nextgen drivetrain has developed. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).
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