Three recalls on the same Allison 10-speed defect. Rear wheel lock-up and tailgate recalls — Silverado 2500HD diesel owners may qualify for a CA buyback.
If you bought a 2020-2022 Chevrolet Silverado 2500HD with the 6.6L Duramax diesel and 10-speed Allison transmission, you may have had a moment on the highway when your truck suddenly downshifted so violently that the rear end skidded sideways. That is not a driver error — it is a documented safety defect. The 10-speed Allison transmission control valve body wears over time, gradually losing hydraulic pressure until, in rare cases, it engages two gears simultaneously and momentarily locks the rear wheels. GM took nearly five years to act, but when it did in October 2024, the recall chain became a cautionary tale in how not to fix a problem. NHTSA recall 24V-797 (October 2024) covered 166,541 Silverado 2500/3500 diesel trucks with a new TCM software fix designed to detect valve wear before lock-up could occur. Then came 25V-148 (February 2025): dealers had installed the wrong software version under 24V-797, leaving those trucks just as vulnerable as before. Then came 26V-083 (February 2026): a narrow group of trucks serviced in a six-day window in December 2024 had received yet another wrong software build. Three recalls. The same defect. The same rear-wheel lock-up risk. The Silverado 2500HD's recall story does not end with the transmission. If you have a power-unlatching tailgate (RPO QT5), two separate recalls — 24V-060 and 24V-894 — cover 2020-2024 trucks whose electronic tailgate switch can be shorted by water, causing the tailgate to drop open while you are driving. And 2024 model year trucks face additional exposure: a steering gear shaft fracture recall (23V-549) and, for a small group, a fuel injector calibration issue. For California owners, this pattern — three cascading recalls on the same transmission defect, repeat wrong-software remedies, and documented near-accidents before the recalls were even issued — is exactly the fact pattern the Song-Beverly Consumer Warranty Act was designed to address.
The issues owners report most, ranked by severity — each one verified against a cited NHTSA source.
Sudden loss of steering — steering wheel no longer controls vehicle direction; grinding or clunking from the front end before full failure; in a fracture event, the pitman arm disconnects and the truck cannot be steered.
Underhood fire or smell of burning electrical components, particularly after rain or water exposure; illuminated brake system warning lights; loss of ABS / traction control function. May occur while vehicle is parked.
Harsh, violent downshifts while driving at highway speed; momentary rear wheel lock-up causing truck to skid or yaw; delayed gear engagement; transmission warning lights or codes (P0747); in severe cases the truck kicks out of gear suddenly and the rear end slides sideways. Symptoms worsen as mileage accumulates.
Tailgate drops open without warning while the truck is moving; cargo slides out of the bed; owner may not notice until items have fallen onto the road. May also unlatch in Park, leaving the gate unsecured before departure. In some cases the tailgate touch-pad switch becomes unresponsive or intermittently triggers on its own.
Rough or unsteady engine idle; higher-than-expected fuel consumption; check engine light with injector-related diagnostic codes; engine may hesitate under load. Owners may notice performance decline compared to early ownership.
A settled Margarian Law case on this exact model, published with the actual settlement math.
Open any defect for the symptoms and why it matters for a California lemon-law claim. Each is tied to a cited NHTSA source.
Harsh, violent downshifts while driving at highway speed; momentary rear wheel lock-up causing truck to skid or yaw; delayed gear engagement; transmission warning lights or codes (P0747); in severe cases the truck kicks out of gear suddenly and the rear end slides sideways. Symptoms worsen as mileage accumulates.
Three cascading recalls (24V-797, 25V-148, 26V-083) on the same valve body defect — including a 'do-over' recall because dealers installed wrong software under the first recall — demonstrate a persistent, systemic failure. Owners who experienced harsh shifts, wheel lock-up events, or were stranded before or after 24V-797 remedy may have strong claims. A truck that momentarily locked its rear wheels at highway speed meets California lemon law's 'safety' prong (2-attempt presumption). Owners whose 24V-797 fix failed (25V-148/26V-083 cohort) have an additional repair visit supporting multi-attempt lemon claims.
Dealers install updated transmission control module (TCM) software that monitors valve wear and limits the transmission to 5th gear when excess wear is detected (preventing the lock-up-inducing downshift from 8th gear). Transmissions identified as having a worn/failed valve body receive valve body or full transmission replacement under a GM special coverage program. Free of charge.
Tailgate drops open without warning while the truck is moving; cargo slides out of the bed; owner may not notice until items have fallen onto the road. May also unlatch in Park, leaving the gate unsecured before departure. In some cases the tailgate touch-pad switch becomes unresponsive or intermittently triggers on its own.
GM received 237+ additional field reports of tailgates opening while driving before issuing the 24V-894 expansion — clear documentation of widespread occurrence. Owners whose tailgate opened while driving (especially at highway speed) and who had repeat tailgate-related dealer visits (e.g., under 24V-060 that did not resolve the problem, then again under 24V-894) have strong multi-repair lemon claims. Ejection of cargo from the bed at highway speed is a direct safety hazard.
Dealers replace the exterior touchpad switch assembly with an updated design. Original recall (24V-060, Feb 2024): new top housing material. Expansion recall (24V-894, Dec 2024): updated switches with wires sealed in butyl tape to prevent electrical shorts. Both repairs free of charge.
Sudden loss of steering — steering wheel no longer controls vehicle direction; grinding or clunking from the front end before full failure; in a fracture event, the pitman arm disconnects and the truck cannot be steered.
Total loss of steering is among the most catastrophic possible vehicle defects. Any 2024 Silverado 2500HD built in the suspect production window that required steering gear inspection or replacement meets the safety-impairment standard. Even a no-fault-found inspection visit counts as a repair attempt under California lemon law. If the truck was out of service pending parts, that time counts toward the 30-day out-of-service threshold.
Dealers inspect the steering gear and replace it if necessary. Free of charge. Owner notification mailed September 22, 2023.
Underhood fire or smell of burning electrical components, particularly after rain or water exposure; illuminated brake system warning lights; loss of ABS / traction control function. May occur while vehicle is parked.
An underhood fire is a catastrophic safety event. Any 2021-2022 Silverado 2500HD that experienced brake system work followed by electrical or fire issues — or that had the BPMV replaced and then experienced repeat brake warning lights — has a documented safety defect. The defect was dealer-introduced during warranty repairs, which strengthens, not weakens, the lemon law claim (the manufacturer's authorized repair network created a dangerous condition).
Dealers replace the entire BPMV assembly. Free of charge. Owner notification November 2021.
Rough or unsteady engine idle; higher-than-expected fuel consumption; check engine light with injector-related diagnostic codes; engine may hesitate under load. Owners may notice performance decline compared to early ownership.
While the per-unit count is small (929 U.S. vehicles), owners of affected 2024 Silverado 2500HDs who reported rough idle or fuel economy complaints and had multiple dealer visits before this recall issued may have lemon claims, particularly if combined with other defects. Rough idle on a diesel truck used for work or towing constitutes a functional impairment.
Dealer performs Fuel Injector Flow Rate Programming using a diagnostic scan tool to update the ECM with improved flow rate data for each installed injector. No parts required. Free of charge.
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Trucks serviced during the six-day window of December 2-8, 2024 under recall 24V-797 may have received an incorrect TCM software version, leaving the valve body failure detection inoperative.
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A subset of vehicles serviced under recall 24V-797 received an incorrect version of TCM software that does not properly detect signs of valve body failure, negating the protective function of the 24V-797 remedy.
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Same root cause as 24V-060: water intrusion into the power tailgate switch assembly causes a short circuit and inadvertent tailgate release. This expansion covers 2024MY HD trucks not captured in the original recall, built after the original suspect window.
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The 10-speed Allison transmission control valve body may experience excess wear over time, causing a gradual loss of hydraulic pressure that produces harsh shifting. In rare cases, pressure loss allows the valve to engage two gears simultaneously, momentarily locking the rear wheels.
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The power-unlatching tailgate's electronic gate-release touchpad switch lacks adequate environmental sealing. Water intrudes into the tailgate housing and contacts the switch, causing a short circuit that triggers the latch solenoid to release — opening the tailgate without driver input.
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Out-of-specification material combined with improper heat treatment at a supplier produced steering gear shafts with metallurgical properties outside GM specifications, making the shaft susceptible to fracture at the pitman arm attachment point.
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During EBCM replacement procedures at dealers, mounting bolts on the brake pressure modulator valve assembly were not properly torqued, destroying the watertight seal between BPMV sub-assemblies. Water that enters the BPMV contacts the brake pressure switch and associated fuse, causing a short circuit.
Every item below comes from this vehicle's documented defects. The more you recognize, the more a free case review is worth your time.
California's Song-Beverly Consumer Warranty Act gives you specific rights when a manufacturer cannot fix a defect after a reasonable number of repair attempts. For safety defects — like momentary rear wheel lock-up at highway speed or a tailgate that opens while driving — California presumes two repair attempts may be enough. For non-safety defects, four or more attempts, or 30 or more cumulative days out of service during the warranty period, can trigger the presumption. If your Silverado 2500HD qualifies, you may be entitled to a full repurchase (the amount you paid, minus a mileage offset), a replacement vehicle of comparable value, or a negotiated cash settlement. GM pays your attorney fees if you prevail — meaning many California lemon law cases cost the owner nothing out of pocket. The three-recall chain on the transmission defect — including repairs that themselves required a follow-up recall — means many owners may already have enough documented dealer visits to meet the threshold. The above is general information only and is not legal advice. Every case turns on its specific facts, dates, and warranty history.
“Could not duplicate” doesn't mean the defect isn't real. Here's exactly what to do to protect a potential California lemon-law claim.
Document the moment it happens. Photos, video, and screenshots of any warning lights — with the date and the mileage.
Get a repair order every visit — even “found nothing.” That paperwork is the foundation of a claim.
Check your VIN at nhtsa.gov/recalls. Note any recall that has no available remedy yet.
Track your out-of-service days. California law counts the cumulative days your vehicle spends in the shop.
Keep loaner & rental records. Alternate-transport paperwork during long repairs matters.
Save everything in one place. Symptoms, dates, repair orders, and every repeat visit — the intermittent ones especially.
Dealers may close repair orders as 'unable to duplicate' (UTD) or 'no trouble found' (NTF) for transmission complaints that are intermittent, or tailgate issues that only occur in rain. Here is what to do: 1. For transmission shudder or harsh shifting: document the exact event — date, mileage, speed, gear you believe the truck was in, and whether you were towing. Take a video if it is safe to do so. The lock-up event may occur only occasionally but the valve wear is progressive, so ask the dealer to inspect the valve body condition and check for TCM software version, not just road-test the truck. 2. Verify your recall software version. After three recalls on the same defect (24V-797, 25V-148, 26V-083), confirm in writing which TCM software build is currently installed and whether your vehicle is involved in any of the three campaigns. A dealer visit to check this — even if UTD — counts as a repair attempt. 3. For tailgate issues: rain exposure triggers the defect. If the dealer says they cannot reproduce it, ask them to test with water applied to the tailgate switch area. Document every occurrence, including any cargo you lost. 4. Request all Diagnostic Trouble Codes in writing. For the transmission, P0747 and related codes may be stored even after the event clears. 5. Keep every repair order — including UTD visits. Under California lemon law, an unsuccessful repair attempt counts toward your threshold regardless of whether the dealer found a fault. 6. For the 2024 MY steering gear recall (23V-549): if your truck was built between June 7 and June 24, 2023, confirm in writing that the steering gear has been inspected and cleared. If inspection reveals a defective shaft and replacement parts require a wait, that out-of-service time counts.
Three recalls on the same 10-speed Allison valve body defect — including two 'do-over' campaigns because the first remedy was incorrectly applied by the dealer network — is extraordinary. At least one NHTSA-documented accident occurred before GM issued the original 24V-797 recall in October 2024. A truck that locks its rear wheels at highway speed while hauling or towing is a serious safety hazard. If your 2020-2022 Silverado 2500HD has been in for any of the three transmission recalls, or if it has been to the dealer for harsh shifting or transmission concerns at any point, pull your service records and find out exactly where your truck stands. The consultation is free and GM covers your attorney fees if you prevail.
— The Margarian Law team
Has your 2020-2022 Silverado 2500HD diesel had harsh shifts, a sudden rear-wheel skid, or been to the dealer for any of the three transmission recalls? Does your truck have a tailgate that has ever opened on its own while driving? Your repair history may already qualify you for a buyback under California law. The consultation is free. Find out what your case is worth.
That event is consistent with the transmission control valve wear defect confirmed by NHTSA recall 24V-797 (October 2024). The 10-speed Allison transmission in the 2020-2022 Duramax diesel Silverado 2500HD and 3500HD uses a hydraulic valve body that is susceptible to excess wear over time. As the valve loses hydraulic pressure, it can actuate more rapidly than intended — and in rare cases it simultaneously engages two gears, locking the rear wheels momentarily. Owners describe the sensation as a violent downshift or a skid, sometimes causing the truck to yaw sideways. The recall covered 166,541 Silverado 2500/3500 diesel trucks. If this has happened to you, document the date, mileage, speed, and whether you were towing — then contact your dealer to check whether any of the three related recalls (24V-797, 25V-148, 26V-083) remain open on your VIN.
Possibly. Two follow-on recalls were issued because the 24V-797 remedy was not always applied correctly. NHTSA recall 25V-148 (February 2025) was issued because a subset of trucks repaired under 24V-797 received an incorrect version of the TCM software — one that could not properly detect the early signs of valve body failure. Then recall 26V-083 (February 2026) addressed a narrower group: trucks serviced during the six-day window of December 2-8, 2024 that received yet another wrong software build. If your truck was serviced under 24V-797, confirm in writing with your dealer which TCM software build is currently installed and whether your VIN is involved in 25V-148 or 26V-083. You can also check at nhtsa.gov using your VIN.
Yes. Two separate recalls cover this defect on 2020-2024 Silverado HD trucks equipped with a power-unlatching tailgate (option code QT5). Recall 24V-060 (February 2024) covered approximately 323,232 Chevrolet Silverado HD and GMC Sierra HD trucks after water was found to intrude into the tailgate's electronic release switch, causing a short circuit that triggers the latch to open without any driver input. An expansion recall, 24V-894 (November 2024), added approximately 132,037 additional 2024 model year trucks after GM received 237 more field reports of inadvertent tailgate openings. GM improved the switch design between the two recalls. If your tailgate has ever dropped open while driving — especially in rain — have your dealer confirm that the updated switch assembly has been installed on your specific truck.
Yes. NHTSA recall 23V-549 (announced September 2023) covered 2,005 Chevrolet Silverado 2500/3500 trucks built between June 7 and June 24, 2023 for a steering gear shaft that may fracture due to out-of-specification material and improper heat treatment at the supplier. If the shaft fractures and the steering arm disconnects, the driver loses all ability to steer the vehicle. GM reported no known field fracture incidents at the time the recall was issued, but total loss of steering is among the most catastrophic possible vehicle defects. If your 2024 Silverado 2500HD was produced in that window, verify with your dealer that the steering gear has been inspected and — if defective — replaced. Even if the inspection came back clean, document that visit; any time your truck is out of service pending recall inspection counts toward the 30-day lemon law threshold.
It may be. NHTSA recall 21V-758 (September 2021) covered 3,241 total Silverado and Sierra HD trucks from model years 2021 and 2022 that had previously received Electronic Brake Control Module (EBCM) replacement at a GM dealer. During that service procedure, the bolts connecting the brake pressure modulator valve (BPMV) to the EBCM were sometimes not torqued to specification, destroying the seal and allowing water to enter the BPMV. The resulting short circuit created an underhood fire risk — two trucks caught fire during rainstorms at the Flint assembly plant before the recall was announced. The remedy was replacement of the BPMV assembly at no charge. This recall is now closed, but if your truck experienced brake warning lights, burning smells, or a fire after an EBCM service visit and the BPMV recall was not performed, you may have both a lemon law and a warranty repair claim.
It may — and the three-recall transmission chain makes the 2020-2022 diesel Silverado 2500HD one of the stronger Chevrolet lemon law fact patterns we see. California's Song-Beverly Consumer Warranty Act presumes a vehicle is a lemon if the manufacturer was unable to fix a safety defect after two or more repair attempts, or any substantial defect after four attempts, or if the truck was out of service for 30 or more cumulative days during the warranty period. For the Silverado 2500HD, owners who went in for a 24V-797 remedy and then learned they needed to return under 25V-148 or 26V-083 already have at least two documented dealer visits for the same underlying defect. A truck that momentarily locked its rear wheels at speed meets the safety prong — which requires only two attempts. Tailgate openings and steering gear recalls add additional documented safety events. Collect every repair order, including recall service records, and consult a California lemon law attorney. GM pays attorney fees if you prevail.
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