GM bulletin 24-NA-088
What it saysThis service bulletin provides diagnostic information for technicians on possible replacement of transmission control valve bodies to correct customer concerns of Malfunction Indicator Lamp (MIL) Illuminated… NHTSA’s full summary ↓
GM filed this with NHTSA as a service bulletin dated Sep 17, 2024, received Jun 18, 2024, about the power train — 3 documents under this number. It names 22 model years across Chevrolet, GMC and Cadillac (2023–2024). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
One page for every brand it was filed under. Each brand’s bulletins: Chevrolet · GMC · Cadillac.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationThis service bulletin provides diagnostic information for technicians on possible replacement of transmission control valve bodies to correct customer concerns of Malfunction Indicator Lamp (MIL) Illuminated, Transmission Not Shifting/Default Mode - DTC P0747 Set.
Trouble codes it names: P0747
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| 24-NA-088 | Service bulletin | Sep 17, 2024 | 11009187 | PDF, 239 KB |
| 24-NA-088 | Service bulletin | May 24, 2024 | 11001776 | PDF, 1,150 KB |
| 24-NA-088 | Service bulletin | May 17, 2024 | 11001761 | PDF, 1,150 KB |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themChevrolet 9 model years
GMC 7 model years
Cadillac 6 model years
A vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 22 model years this bulletin names have filed 2,768 complaints with NHTSA since 2015. 589 of them name Power Train — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
Sudden jerk power train and deceleration while driving and towing 5th wheel, immediate loss of power and could have been catastrophic. GM has a known defect that requires immediate attention and investigation to affirm this is a broad national problem with the Allison 10 speed 10L1000 transmission, specifically the defective transmission…
2023 Chevrolet Silverado 2500HD · Power Train · filed with NHTSA Jul 8, 2025
The valve body assembly is not letting it to shift right when driving from 50mph to 60 mph it has a clunking noise I have it replaced and is still not working correctly GM knows there is a problem with the 10 speed transmissions I have a 2023 3500 diesel with the same problem as the recalls on the 2020 to 2022 years It is doing the same…
2023 Chevrolet Silverado 3500HD · Power Train · filed with NHTSA Jun 27, 2026
August of 2025 purchased a certified GMC Sierra 3500. The truck had been traded in May and sat in their service department waiting on a valve body. At this point, we knew this. had done research on it, and felt confident in being told the valve body was completely replaced and now working…. Worst mistake we’ve made in a long time.
2023 GMC Sierra 3500HD · Power Train · filed with NHTSA Feb 24, 2026
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the power train
Source: same model, same component group130 other manufacturer communications filed against these GM models under the same component group (power train), newest first. The eight newest are listed; the rest are on the Chevrolet list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| N262567720 | Service campaign | Sep 17, 2026 | Certain vehicles may have received transmission mounting bolts that do not meet expected hardness specifications. Loose or failed bolts may… |
| N252502891-01 | Service campaign | Aug 20, 2026 | Certain vehicles may have a condition in which the internal differential nut was cross threaded or missing during assembly. Dealers will rev… |
| N262560680 | Service campaign | Jun 10, 2026 | Certain vehicles may have a condition in which the bolts for the transmission control valve body may be loose or missing. Dealers will retor… |
| N252517790 | Service campaign | Oct 14, 2025 | Certain vehicles, equipped with 8L80 or 8L90 Transmissions, may have a condition in which the reaction carrier cracks. Dealers are to replac… |
| N242454441 -03 | Service campaign | Oct 9, 2025 | Certain vehicles listed above, may have a condition where the transmission control valve has worn, resulting in a gradual loss of pressure w… |
| 25-NA-080 | Service bulletin | Sep 4, 2025 | This service bulletin provides a procedure to overhaul the control valve to replace a plate and worn down check ball to correct the customer… |
| N252494003-01 | Service campaign | Jun 26, 2025 | Certain vehicles listed above, may have a condition where the connecting rod and/or crankshaft engine components in these vehicles may have… |
| 24-NA-262 | Service bulletin | Jun 3, 2025 | This bulletin helps aid the tech in possible 10L100 transmission noise that may be normal or abnormal depending on the concern noted. |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Chevrolet, GMC and Cadillac, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is GM 24-NA-088 a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the 24-NA-088 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way.
Which vehicles does 24-NA-088 cover?
The manufacturer filed it against 22 model years across 3 brands (Chevrolet, GMC and Cadillac): 2024 Cadillac CT4, 2023 Cadillac CT4, 2024 Cadillac CT5, 2023 Cadillac CT5, 2024 Cadillac Escalade, 2023 Cadillac Escalade and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.