The tariff classification of tensioner assembly from South Korea

N361649May 28, 2026CLA-2-84:OT:RR:NC:N2:201
CATEGORY: Classification
TARIFF NO.: 8409.91.5085
Mr. Jae Young SonHyundai Motor Company231, Yangjae-dong, Seocho-guSeoul, 06797South KoreaRE: The tariff classification of tensioner assembly from South KoreaDear Mr. Son:In your letter dated
May 19, 2026
, you requested a tariff classification ruling.The item under consideration has been identified as the tensioner assembly-O/P & BS Chain, Part number24460-2T500, used in the THETA3 engine.The subject item is a component of an automobile engine designed to maintain proper tension in the drivechain that transmits power from the crankshaft to the oil pump and balance shaft. It features an integrateddesign in which the tensioner and the tensioner arm are combined, with the shoe and plate base collectivelyperforming the function of the tensioner arm.Theis a key component that maintains a proper tension on the OP&BS drive chain, which tensioner assembly transmits motive power from the crankshaft to the oil pump and balance-shaft, thereby ensuring stable powertransmission through the chain.The timing chain system consists of a driver side and a non-driven side, each exhibiting different characteristics depending on the chain’s tensile load and the operating characteristics ofthe tensioner.Driver side: the side that directly transmits motive power from the crankshaft to the oil pump andbalance shaft. It is always under tension during engine operation and bears the largest tensile load onthe chain.Non-driven side: the return side to the crankshaft after power transmission. It is more prone to slackthan the driver side and requires a separate tensioning mechanism.The subject item is installed on the non-driven side and maintains the tension of the drive chain between thecrankshaft and the oil pump and balance-shaft, thereby preventing chain slack and contributing to stable
power transmission and maintaining proper phase relationship in the drive train.y maintaining proper Btension in the OP/BS chain, the subject item enables proper operation of the oil pump, thereby ensuringsmooth oil circulation throughout the engine and preventing performance degradation and engine damage.During driving, the chain tension fluctuates continuously with changes in engine speed (RPM), causing theplunger to undergo repeated minute advance and retraction movements. During this process, when theplunger retracts, the hydraulic pressure in the internal oil chamber of the subject item is compressed,performing a dampening function and thereby absorbing the impact. By maintaining the OP/BS chain at itsoptimal tension, the subject item minimizes friction and impact on the sprocket and accommodates chainwear and elongation, thereby improving the durability and service life of both the chain and the sprocket.In your request you suggest classification of the tensioner assembly in 8409.91.5085, Harmonized TariffSchedule of the United States (HTSUS), which provides for “Parts suitable for use solely or principally withthe engines….” We agree.The applicable subheading for the tensioner assembly-O/P & BS Chain, Part number 24460-2T500, will be8409.91.5085, HTSUS, which provides for “Parts suitable for use solely or principally with the engines ofheading 8407 or 8408: Other: Suitable for use solely or principally with spark-ignition internal combustionpiston engines (including rotary engines): Other: Other: Other.” The general rate of duty will be 2.5% advalorem.The duties cited above are current as of this ruling’s issuance. Duty rates are provided for your convenienceand are subject to change. The text of the most recent HTSUS and the accompanying duty rates are providedat https://hts.usitc.gov/.This ruling does not address the applicability of any additional duties, taxes, fees, exactions and/or othercharges, which may apply to the goods discussed herein. This includes, but is not limited to, tariffs and otherduties as provided for in Subchapter III to Chapter 99, HTSUS. Thus, for example, in addition to theclassification stated above, the merchandise covered by this ruling may also need to be reported with eitherthe Chapter 99 provision under which an additional tariff applies or one of the Chapter 99 provisionscovering exceptions to such tariffs.For further information to assist with the importation process, please refer to the frequently updated CargoSystems Messaging Service (CSMS) messages at https://www.cbp.gov/trade/automated/cargo-systems-messaging-service and the Trade Remedies page at https://www.cbp.gov/trade/programs-administration/trade-remedies.The holding set forth above applies only to the specific factual situation and merchandise description asidentified in the ruling request. This position is clearly set forth in Title 19, Code of Federal Regulations(CFR), Section 177.9(b)(1). This section states that a ruling letter is issued on the assumption that all of theinformation furnished in the ruling letter, whether directly, by reference, or by implication, is accurate andcomplete in every material respect. In the event that the facts are modified in any way, or if the goods do notconform to these facts at time of importation, you should bring this to the attention of U.S. Customs andBorder Protection (CBP) and submit a request for a new ruling in accordance with 19 CFR 177.2. Additionally, we note that the material facts described in the foregoing ruling may be subject to periodicverification by CBP.This ruling is being issued under the provisions of Part 177 of the Customs and Border ProtectionRegulations (19 C.F.R. 177).
A copy of the ruling or the control number indicated above should be provided with the entry documentsfiled at the time this merchandise is imported. If you have any questions regarding the ruling, please contactNational Import Specialist Matthew Sullivan at [email protected].
Sincerely,
(for)James P. ForkanDirectorNational Commodity Specialist Division