{"product_id":"deck-belt-m154960","title":"M154960 \/ M143923 Deck Belt for John Deere 54-Inch Deck","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eThis aftermarket \u003cstrong\u003eM154960 \/ M143923 mower deck belt\u003c\/strong\u003e fits select John Deere tractors equipped with compatible 54-inch mower decks using the listed replacement belt-number path.\u003c\/p\u003e\n\u003cp\u003eThe supplier lists this replacement belt at approximately \u003cstrong\u003e120.7 inches long by 0.60 inch wide\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003eOn compatible two-belt mower decks, M154960 \/ M143923 is commonly used as the \u003cstrong\u003esecondary spindle-drive belt\u003c\/strong\u003e that routes through the mower-deck spindle and idler pulley system. A separate primary belt may transfer power from the PTO clutch to the mower deck.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eAftermarket mower-deck drive belt\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrimary Replacement Number:\u003c\/strong\u003e M154960\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdditional Replacement Number:\u003c\/strong\u003e M143923\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupplier Reference:\u003c\/strong\u003e BT434A1004\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupplier-Listed Length:\u003c\/strong\u003e 3065.7 mm \/ approximately 120.7 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupplier-Listed Width:\u003c\/strong\u003e 15.25 mm \/ approximately 0.60 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Polyester\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCover Style:\u003c\/strong\u003e Dry cover\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e Gray\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuantity Included:\u003c\/strong\u003e One belt\u003c\/li\u003e\n\u003cli\u003eUsed on select John Deere 54-inch mower-deck configurations\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch2\u003eReplaces These Belt Numbers\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eM143923\u003c\/li\u003e\n\u003cli\u003eM154960\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSupplier Reference Number\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBT434A1004\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSearch-Friendly Number Formats\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eM143923\u003c\/li\u003e\n\u003cli\u003e143923\u003c\/li\u003e\n\u003cli\u003eM154960\u003c\/li\u003e\n\u003cli\u003e154960\u003c\/li\u003e\n\u003cli\u003eBT434A1004\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch2\u003eBelt Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eComponent:\u003c\/strong\u003e Mower-deck drive belt\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLength:\u003c\/strong\u003e 3065.7 mm \/ approximately 120.7 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWidth:\u003c\/strong\u003e 15.25 mm \/ approximately 0.60 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Polyester\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCover:\u003c\/strong\u003e Dry cover\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e Gray\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuantity:\u003c\/strong\u003e One belt\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003ePublished belt measurements can vary depending on how the belt is measured. Use the original \u003cstrong\u003eM154960 or M143923\u003c\/strong\u003e number as the primary fitment check rather than relying on a tape measurement alone.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eCompatible John Deere Model Paths\u003c\/h2\u003e\n\u003cp\u003eThe supplier associates the M154960 \/ M143923 belt with select 54-inch mower-deck configurations in the following John Deere model families:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eJohn Deere X320\u003c\/li\u003e\n\u003cli\u003eJohn Deere X340\u003c\/li\u003e\n\u003cli\u003eJohn Deere X590\u003c\/li\u003e\n\u003cli\u003eJohn Deere GX325\u003c\/li\u003e\n\u003cli\u003eJohn Deere GX355\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFitment note:\u003c\/strong\u003e These are supplier-provided model examples. The belt fits only the mower-deck configurations that use M154960 or M143923. Confirm the original belt number and installed deck before ordering.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eJohn Deere X320 Fitment Note\u003c\/h2\u003e\n\u003cp\u003eThe M154960 \/ M143923 belt is used on select John Deere X320 tractors equipped with a compatible \u003cstrong\u003e54-inch mower deck\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003eOn the compatible two-belt deck path:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eThe short primary belt transfers power from the PTO clutch to the mower deck.\u003c\/li\u003e\n\u003cli\u003eThe M154960 \/ M143923 secondary belt routes through the spindle and idler pulley system.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThis listing includes the M154960 \/ M143923 belt only. It does not include the separate primary mower-deck belt.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eJohn Deere X340 Fitment Note\u003c\/h2\u003e\n\u003cp\u003eThe supplier associates this belt with select John Deere X340 tractors equipped with compatible 54-inch mower decks.\u003c\/p\u003e\n\u003cp\u003eJohn Deere X340 tractors may be found with more than one mower-deck configuration. Confirm that the original belt is marked \u003cstrong\u003eM154960 or M143923\u003c\/strong\u003e.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eJohn Deere X590 Fitment Note\u003c\/h2\u003e\n\u003cp\u003eThe supplier lists select John Deere X590 54-inch mower-deck configurations among the compatible applications.\u003c\/p\u003e\n\u003cp\u003eConfirm the mower-deck configuration, original belt number, and belt routing before ordering. Do not select the belt from the X590 model name alone.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eJohn Deere GX325 and GX355 Fitment Note\u003c\/h2\u003e\n\u003cp\u003eThe supplier associates M154960 \/ M143923 with select John Deere GX325 and GX355 tractors using compatible 54-inch mower decks.\u003c\/p\u003e\n\u003cp\u003eThese tractor families were available with different mower-deck sizes and configurations. Match the original belt number and installed deck before ordering.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003ePrimary Belt vs. Secondary Belt\u003c\/h2\u003e\n\u003cp\u003eMany compatible John Deere 54-inch mower decks use two separate belts:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eThe \u003cstrong\u003eprimary deck belt\u003c\/strong\u003e transfers power from the engine-mounted PTO clutch to the mower deck.\u003c\/li\u003e\n\u003cli\u003eThe \u003cstrong\u003esecondary deck belt\u003c\/strong\u003e routes through the mower-deck spindle and idler pulleys.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eM154960 \/ M143923 is commonly used in the \u003cstrong\u003esecondary spindle-drive position\u003c\/strong\u003e on compatible two-belt deck systems.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eCommon Symptoms of a Worn Secondary Deck Belt\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eThe primary belt turns but the mower blades do not rotate correctly\u003c\/li\u003e\n\u003cli\u003eOne or more blades turn slowly under mowing load\u003c\/li\u003e\n\u003cli\u003eThe belt squeals when the PTO clutch engages\u003c\/li\u003e\n\u003cli\u003eThe belt repeatedly jumps off a spindle or idler pulley\u003c\/li\u003e\n\u003cli\u003eVisible cracking, glazing, fraying, or burned belt surfaces\u003c\/li\u003e\n\u003cli\u003eLoose belt tension with the tension arm engaged\u003c\/li\u003e\n\u003cli\u003eUneven blade speed across the mower deck\u003c\/li\u003e\n\u003cli\u003eReduced grass-discharge or bagging performance\u003c\/li\u003e\n\u003cli\u003eBurning-rubber smell near the mower deck\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003ePark the mower on a level surface and remove the ignition key.\u003c\/li\u003e\n\u003cli\u003eDisconnect the spark-plug leads before working near the mower deck.\u003c\/li\u003e\n\u003cli\u003ePhotograph or sketch the original belt routing before removal.\u003c\/li\u003e\n\u003cli\u003eIdentify the primary and secondary mower-deck belts before disassembly.\u003c\/li\u003e\n\u003cli\u003eInspect each spindle pulley and idler pulley for bearing wear.\u003c\/li\u003e\n\u003cli\u003eInspect the tension arm, tension spring, and belt guides.\u003c\/li\u003e\n\u003cli\u003eConfirm the flat and V-shaped sides of the belt contact the correct pulleys.\u003c\/li\u003e\n\u003cli\u003eMake sure the belt is seated completely inside every pulley groove.\u003c\/li\u003e\n\u003cli\u003eRotate the mower-deck pulley system manually before starting the engine.\u003c\/li\u003e\n\u003cli\u003eReplace seized pulleys or damaged tension components before operating the new belt.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch2\u003eQuick Ship Fulfillment\u003c\/h2\u003e\n\u003cp\u003eThis item may ship directly from one of our trusted U.S. distribution partners to help reduce transit time. Packaging, labeling, or warehouse origin may vary, but the part will match the replacement numbers, fitment notes, and supplier specifications shown in this listing.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eWhy Buy From PTO Direct USA\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003ePart-number-first listings to help reduce fitment mistakes\u003c\/li\u003e\n\u003cli\u003eFocused mower-deck and PTO replacement parts\u003c\/li\u003e\n\u003cli\u003eClear primary and secondary belt-position notes\u003c\/li\u003e\n\u003cli\u003ePractical support when you need help checking compatibility\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch2\u003eFAQ\u003c\/h2\u003e\n\u003ch3\u003eWhat does the M154960 belt replace?\u003c\/h3\u003e\n\u003cp\u003eThe supplier cross-references this aftermarket belt to John Deere numbers \u003cstrong\u003eM154960 and M143923\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch3\u003eIs M154960 the same replacement path as M143923?\u003c\/h3\u003e\n\u003cp\u003eYes. This supplier belt is listed as a replacement for both M154960 and M143923 when the mower-deck configuration and dimensions match.\u003c\/p\u003e\n\u003ch3\u003eHow long is the supplier-listed M154960 belt?\u003c\/h3\u003e\n\u003cp\u003eThe supplier lists the belt at \u003cstrong\u003e3065.7 mm long\u003c\/strong\u003e, approximately \u003cstrong\u003e120.7 inches\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch3\u003eHow wide is the supplier-listed M154960 belt?\u003c\/h3\u003e\n\u003cp\u003eThe supplier lists the belt at \u003cstrong\u003e15.25 mm wide\u003c\/strong\u003e, approximately \u003cstrong\u003e0.60 inch\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch3\u003eWhat material is the belt made from?\u003c\/h3\u003e\n\u003cp\u003eThe supplier describes the belt as a polyester replacement belt with a dry cover.\u003c\/p\u003e\n\u003ch3\u003eHow many belts are included?\u003c\/h3\u003e\n\u003cp\u003eThis listing includes \u003cstrong\u003eone M154960 \/ M143923 mower-deck belt\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch3\u003eIs M154960 a primary or secondary deck belt?\u003c\/h3\u003e\n\u003cp\u003eOn compatible two-belt John Deere 54-inch mower decks, M154960 \/ M143923 is commonly used as the \u003cstrong\u003esecondary spindle-drive belt\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch3\u003eDoes this listing include the primary mower-deck belt?\u003c\/h3\u003e\n\u003cp\u003eNo. This listing includes one M154960 \/ M143923 belt only. A separate primary belt may be required.\u003c\/p\u003e\n\u003ch3\u003eDoes M154960 fit the John Deere X320?\u003c\/h3\u003e\n\u003cp\u003eThe supplier associates this belt with select John Deere X320 tractors equipped with compatible 54-inch mower decks. Confirm the original belt number before ordering.\u003c\/p\u003e\n\u003ch3\u003eDoes M154960 fit the John Deere X340?\u003c\/h3\u003e\n\u003cp\u003eThe supplier lists select X340 54-inch mower-deck applications. Match the original M154960 or M143923 number and deck routing.\u003c\/p\u003e\n\u003ch3\u003eDoes M154960 fit the John Deere X590?\u003c\/h3\u003e\n\u003cp\u003eThe supplier associates the belt with select X590 54-inch mower-deck configurations. Not every X590 deck uses this belt.\u003c\/p\u003e\n\u003ch3\u003eDoes M154960 fit the John Deere GX325?\u003c\/h3\u003e\n\u003cp\u003eThe supplier lists select GX325 tractors with compatible 54-inch mower decks. Confirm the original belt number and installed deck.\u003c\/p\u003e\n\u003ch3\u003eDoes M154960 fit the John Deere GX355?\u003c\/h3\u003e\n\u003cp\u003eThe supplier lists select GX355 tractors with compatible 54-inch mower decks. Match the original belt number before ordering.\u003c\/p\u003e\n\u003ch3\u003eIs this the tractor traction-drive belt?\u003c\/h3\u003e\n\u003cp\u003eNo. This listing is for a mower-deck drive belt. The traction-drive belt that moves the tractor is a separate part.\u003c\/p\u003e\n\u003ch3\u003eCan I order this belt using only the mower model?\u003c\/h3\u003e\n\u003cp\u003eNo. Confirm the original belt number, mower-deck size, belt position, supplier-listed dimensions, and pulley routing before ordering.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003eRelated John Deere Parts and Guides\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/products\/pto-clutch-am141536\"\u003eAM141536 PTO Clutch Replacement\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/deck-belt-m154897\"\u003eM154897 \/ M172924 Primary Deck Belt\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/spindle-assembly-am144377\"\u003eAM144377 Spindle Assembly\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/john-deere-quick-reference\/john-deere-x320\"\u003eJohn Deere X320 Quick Reference\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003cp\u003e\u003cstrong\u003eNeed a different belt?\u003c\/strong\u003e Browse the full \u003ca href=\"\/collections\/belts\"\u003emower deck belts collection\u003c\/a\u003e.\u003c\/p\u003e","brand":"PTO Direct USA","offers":[{"title":"Default Title","offer_id":53200255844719,"sku":"CAL-295873873198","price":34.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0957\/5058\/6735\/files\/M154960-belt.jpg?v=1783914294","url":"https:\/\/ptodirectusa.com\/products\/deck-belt-m154960","provider":"PTO Direct USA","version":"1.0","type":"link"}