{"nhtsa_id":11031193,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2026-04-08","date":"2026-03-27","document_id":"IK1900301","mfr_campaign":null,"replaces":null,"component":"ENGINE","mfr_system":null,"summary":"The purpose of this article is to provide the user with the necessary tools and related manuals to maintain, diagnose, and repair an Espar Hydronic S3 Heater (GEN 3). The Espar Hydronic S3 (GEN 3) Auxiliary Heater is a diesel-fired coolant heater for maintaining cabin heat without running the engine. The heater uses fuel from the fuel tank to heat coolant before it goes to the heater core in the sleeper HVAC unit. The heater is located under the cab's sleeper area and is powered by the vehicle's batteries.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2026/MC-11031193-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2026/MC-11031193-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/11031193","components":[{"id":"engine","name":"Engine","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"INTERNATIONAL","model":"LT","year_from":2023,"year_to":2026,"match":null,"vehicle_ids":[]}],"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":[]}