{"nhtsa_id":11026416,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2025-12-05","date":"2025-11-04","document_id":"01-090","mfr_campaign":"01-090","replaces":null,"component":"ENGINE","mfr_system":null,"summary":"Repair procedures and warranty information for model 520EV are now available. The cab heater coolant system on Peterbilt 579EV and 520EV models may not deaerate properly, causing pump malfunctions and inadequate cab heating. Update coolant deaeration return line parts and procedures are now available to release trapped air back to the reservoir.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11026416-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11026416-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/11026416","components":[{"id":"engine","name":"Engine","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"PETERBILT","model":"520","year_from":2021,"year_to":2026,"match":"exact","vehicle_ids":["2021_peterbilt_520","2022_peterbilt_520","2023_peterbilt_520","2024_peterbilt_520","2025_peterbilt_520","2026_peterbilt_520"]},{"make":"PETERBILT","model":"579","year_from":2021,"year_to":2026,"match":"exact","vehicle_ids":["2021_peterbilt_579","2022_peterbilt_579","2023_peterbilt_579","2024_peterbilt_579","2025_peterbilt_579","2026_peterbilt_579"]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}