Recall 21V194 covers 258 2015-2021 medium-duty vehicles for loose rear axle U-bolt nuts. Repair is free at any franchised Chevrolet dealer.
Chevrolet is recalling 258 2015-2021 5500HD, 4500XD, and related Isuzu medium-duty trucks because rear axle U-bolt nuts were not properly tightened and can loosen, shifting the axle out of alignment. That misalignment can separate the propeller shaft, cut power to the rear wheels, and stall the vehicle, increasing crash risk; Chevrolet dealers will complete the free repair.
Does this recall apply to your specific vehicle?
The official, free per-VIN recall check is run by NHTSA. Enter your VIN and we'll forward you directly — and add you to a free watchlist so you hear about new recalls for your vehicle.
Check my VIN at NHTSARecallNotify doesn't check your VIN — NHTSA's official tool does. We use your email only to alert you to new recalls.
Watch this vehicle for recalls
Add it to your free watchlist and we will alert you as new federal recalls are posted for your year, make and model. New-recall alerts are rolling out now.
You are on the watchlist.
We will email you as new federal recalls are posted for your vehicle.
What's wrong?
The rear axle U-bolts on affected 2015-2021 Chevrolet trucks clamp the rear axle to the leaf spring suspension. Leaf springs support the truck's weight and help keep the axle positioned under the frame. The U-bolts and nuts hold that axle in place under load, braking, and road vibration.
On these trucks, the rear axle U-bolt nuts were not confirmed as properly tightened at the plant. The tool used on the assembly line gave misleading tightening information, so workers were led to believe the nuts were tight enough. If the nuts loosen, the rear axle can shift out of alignment and the propeller shaft can separate during use.
A driver can see the rear axle out of place during a pre-trip inspection. If the propeller shaft separates while driving, the driver would hear a loud noise.
Who's affected?
Spans Chevrolet, International Motors, and Isuzu medium-duty trucks from 2015-2021, all tied to the rear leaf-spring U-bolt hardware.
| 2017 Chevrolet 5500HD | rear suspension |
|---|---|
| 2017 Chevrolet 4500XD | rear suspension |
| 2020 International Motors Chevy 5500HD | rear suspension |
| 2020 International Motors Chevy 4500HD | rear suspension |
| 2019 International Motors Chevy 5500HD | rear suspension |
| 2019 International Motors Chevy 4500HD | rear suspension |
| 2018 Chevrolet 5500HD | rear suspension |
| 2018 Chevrolet 4500XD | rear suspension |
| 2018 Chevrolet 4500HD | rear suspension |
| 2020 Isuzu Npr Xd | rear suspension |
| 2020 Isuzu Npr Hd | rear suspension |
| 2020 Chevrolet 5500XD | rear suspension |
| 2020 Chevrolet 4500XD | rear suspension |
| 2020 Chevrolet 5500HD | rear suspension |
| 2019 Chevrolet 5500HD | rear suspension |
| 2020 Chevrolet 4500HD | rear suspension |
| 2019 Chevrolet 4500HD | rear suspension |
| 2020 Isuzu Nrr | rear suspension |
| 2020 Isuzu Nqr | rear suspension |
| 2019 Isuzu Nqr | rear suspension |
| 2019 Isuzu Npr Xd | rear suspension |
| 2019 Isuzu Npr Hd | rear suspension |
| 2018 Isuzu Nrr | rear suspension |
| 2018 Isuzu Nqr | rear suspension |
| 2018 Isuzu Npr Xd | rear suspension |
| 2018 Isuzu Npr Hd | rear suspension |
| 2017 Isuzu Npr | rear suspension |
| 2017 Isuzu Nrr | rear suspension |
| 2017 Isuzu Nqr | rear suspension |
| 2017 Isuzu Npr Xd | rear suspension |
| 2017 Isuzu Npr Hd | rear suspension |
| 2017 Isuzu Reach | rear suspension |
| 2016 Isuzu Reach | rear suspension |
| 2015 Isuzu Reach | rear suspension |
| 2016 Isuzu Nrr | rear suspension |
| 2016 Isuzu Nqr | rear suspension |
| 2016 Isuzu Npr Xd | rear suspension |
| 2016 Isuzu Npr Hd | rear suspension |
| 2016 Isuzu Npr | rear suspension |
| 2015 Isuzu Npr | rear suspension |
| 2017 Chevrolet 4500HD | rear suspension |
| 2019 Chevrolet 4500XD | rear suspension |
| 2021 Isuzu Nrr | rear suspension |
| 2019 Isuzu Nrr | rear suspension |
| Units affected | 258 |
| Field incidents | NHTSA has logged 2 field incidents to date. |
The year and model narrow the scope, but the VIN decides. Check your VIN to confirm whether your specific truck is included.
What's the safety risk?
A misaligned rear axle can let the propeller shaft separate, cutting power to the rear wheels and causing a stall, which increases crash risk. During inspection, look for a rear axle that sits out of place. A separated shaft also makes a loud noise during use. Schedule the inspection and repair soon. Repair is free at any franchised Chevrolet dealer.
What should I do?
- Check your VIN to confirm your 2015-2021 Chevrolet 5500HD, 4500XD, Chevy 5500HD, Chevy 4500HD, 4500HD, Npr Xd, Npr Hd, 5500XD, Nrr, Nqr, Npr, or Reach is included in this recall.
- Contact a franchised Chevrolet dealer to schedule the free rear-axle U-bolt-nut inspection and tightening or replacement that prevents axle misalignment.
- Bring any recall notice you received. If not, reference recall number 21V194 when you call.
- Avoid heavy hauling until the repair is complete, and stop driving if the truck loses rear-wheel power or stalls.
What happens at the repair
At the dealer, a Chevrolet technician inspects the rear axle U-bolt nuts, replaces any damaged or loose nuts, and tightens the hardware to the required specification. Parts and labor are free under the recall. Isuzu says the reported work fell within the warranty period and U-bolt nut tightening is part of regular service, so prior out of pocket repairs are handled through warranty or regular service coverage, not a separate reimbursement program. Ask the service desk how that coverage applies if you have prior repair paperwork.
| Reimbursement | Warranty coverage applies |
|---|
Timeline
| March 19, 2021 | NHTSA published the recall |
|---|---|
| March 19, 2021 | Dealer notification began |
| March 19, 2021 | Dealer notification ended |
| April 23, 2021 | Owner notification mailed |
| April 23, 2021 | VIN-searchable in NHTSA's database — Check your VIN to see whether this recall applies to your specific vehicle. |
| April 23, 2021 | Interim owner notification (was planned for this date) |
Frequently asked questions
What is recall 21V194?
Recall 21V194 covers 258 2015-2021 Chevrolet medium-duty vehicles with rear axle U-bolt nuts that were not tightened correctly. The nuts can loosen, the axle can shift out of alignment, and the propeller shaft can separate, causing loss of power to the rear wheels and a stall.
What should I do if my 2015-2021 Chevrolet 5500HD, 4500XD, Chevy 5500HD, Chevy 4500HD, 4500HD, Npr Xd, Npr Hd, 5500XD, Nrr, Nqr, Npr, or Reach is on this recall?
Check your VIN to confirm your specific vehicle is included in recall 21V194. If it is, contact a franchised Chevrolet dealer and ask for the rear axle U-bolt nut inspection under recall 21V194. The dealer will replace and tighten the nuts if needed.
Is the recall repair free?
Yes. Federal recall law requires the recall repair to be performed at no cost. For recall 21V194, dealers will inspect the rear axle U-bolt nuts and, if needed, replace and tighten them free of charge.
Is it safe to drive before the repair?
The recall does not include a do-not-drive order. The safety risk is that a loose rear axle U-bolt nut can let the axle misalign, which can separate the propeller shaft, cut power to the rear wheels, and stall the vehicle. Check your VIN and schedule the free repair if included.
When did recall 21V194 repairs begin?
Repairs for recall 21V194 began on April 23, 2021. If your VIN is included and the repair has not been completed, call a franchised Chevrolet dealer and reference recall 21V194 or Isuzu recall number V2103.
More information
| NHTSA campaign page | nhtsa.gov/vehicle-recalls/21V194000 |
|---|---|
| Chevrolet customer service | 1-866-441-9638 |
| NHTSA recall # | 21V194 |
| NHTSA recall # (full) | 21V194000 |
Source documents
-
Download Recall Document (PDF) (PDF) - Download Recall Document (PDF) (PDF)
- Download Quarterly Report (PDF)
- Download Misc. Document (PDF)
- Download Recall Investigation Document (PDF) (PDF)
- Download Owner Notification Letter (PDF)
- Download Owner Notice (PDF)
- Download Recall Report (PDF)
- Download Recall Acknowledgement (PDF)
This article is generated from NHTSA's primary recall filings and reviewed against the source on May 23, 2026. RecallNotify does not paraphrase NHTSA's consequence language; that text is reproduced as written above. Editorial standards →