{"product_id":"cummins-3256759-aftermarket-alternator","title":"Cummins 3256759 Aftermarket Alternator","description":"\u003cdiv style=\"font-family:Roboto,sans-serif;color:#1a1a1a;line-height:1.6\"\u003e\n\u003cstyle\u003e@import url('https:\/\/fonts.googleapis.com\/css2?family=Roboto+Condensed:wght@700\u0026family=Roboto:wght@400;700;900\u0026display=swap');.spm-c{border:1px solid #d1d1d1;background:#fff;margin-bottom:25px;overflow:hidden}.spm-h{padding:15px 20px;background:#ffce02;border-bottom:1px solid #d1d1d1;font-weight:900;text-transform:uppercase;font-size:16px;color:#000;letter-spacing:.05em;font-family:'Roboto Condensed',sans-serif}.spm-t{width:100%;border-collapse:collapse;font-size:15px}.spm-t th{padding:12px 10px;text-align:left;background:#f4f4f4;font-size:12px;text-transform:uppercase;letter-spacing:.04em;border-bottom:1px solid #d1d1d1;color:#000}.spm-t td{padding:11px 10px;border-bottom:1px solid #eee;text-align:left;vertical-align:top}.spmL{font-weight:700;color:#333;background:#fcfcfc;width:38%}.spm-sub{display:block;color:#777;font-size:12.5px;margin-top:2px}.spm-chip{display:inline-block;margin:0 8px 8px 0;padding:6px 12px;border:1px solid #d1d1d1;background:#fcfcfc;font-size:14px;font-weight:700;color:#000}.spm-h2{font-family:'Roboto Condensed',sans-serif;font-size:24px;font-weight:900;color:#000;text-transform:uppercase;margin:40px 0 20px;letter-spacing:.05em;border-bottom:3px solid #ffce02;padding-bottom:15px}.spm-p{font-size:16px;line-height:1.8;margin:0 0 18px}@media(max-width:700px){.spmL{width:auto}}\u003c\/style\u003e\n\u003cp class=\"spm-p\"\u003eCummins 3256759 is the 28 volt, 55 amp alternator with an eight rib poly V pulley, black cooling fan, cast aluminium housings with a top lug and a mounting foot, and a rear regulator with B+, D+ and W terminals. It is used on Cummins 6CT8.3 engines. This aftermarket version has the same mounting and electrical connector as the original, so it plugs in and bolts on where the old one came off.\u003c\/p\u003e\n\u003cp class=\"spm-p\"\u003eThe same part is also sold as Cummins 3251385 and 3964745.\u003c\/p\u003e\n\u003cp class=\"spm-p\"\u003eSold as one unit. Check the number on your old part, or in the parts manual for your machine, before ordering.\u003c\/p\u003e\n\u003ch2 class=\"spm-h2\"\u003eTechnical Properties \u0026amp; Sizes\u003c\/h2\u003e\n\u003cdiv class=\"spm-c\"\u003e\n\u003cdiv class=\"spm-h\"\u003eSpecifications\u003c\/div\u003e\n\u003ctable class=\"spm-t\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003ePart Type\u003c\/td\u003e\n\u003ctd\u003eAlternator\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eReplaces\u003c\/td\u003e\n\u003ctd\u003eCummins 3964745\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eEngine\u003c\/td\u003e\n\u003ctd\u003eCummins 6CT8.3, 6CT8.3-D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eOutput\u003c\/td\u003e\n\u003ctd\u003e28 V, 55 A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eCross References\u003c\/td\u003e\n\u003ctd\u003eCummins 3251385, 3256759\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eFits\u003c\/td\u003e\n\u003ctd\u003eCummins 6CT8.3 and 6CT8.3-D diesel engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eCondition\u003c\/td\u003e\n\u003ctd\u003eNew, aftermarket\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eStat. HS-Code\u003c\/td\u003e\n\u003ctd\u003e851150\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"spmL\"\u003eCountry of Manufacture\u003c\/td\u003e\n\u003ctd\u003eChina\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spm-c\"\u003e\n\u003cdiv class=\"spm-h\"\u003eCompatibility\u003c\/div\u003e\n\u003cdiv style=\"padding:20px\"\u003e\n\u003cp style=\"margin:0 0 10px;font-weight:700;color:#333\"\u003eCummins machines\u003c\/p\u003e\n\u003cdiv\u003e\u003cspan class=\"spm-chip\"\u003eCummins 6CT8.3 and 6CT8.3-D diesel engines\u003c\/span\u003e\u003c\/div\u003e\n\u003cp style=\"font-size:13px;color:#666;margin:0 0 18px\"\u003eCheck the part number on your old unit before ordering.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spm-c\"\u003e\n\u003cdiv class=\"spm-h\"\u003ePart Numbers\u003c\/div\u003e\n\u003cdiv style=\"overflow-x:auto\"\u003e\u003ctable class=\"spm-t\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eCummins Part No.\u003cspan class=\"spm-sub\"\u003e(SPM Part No.)\u003c\/span\u003e\n\u003c\/th\u003e\n\u003cth\u003eFits\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e3964745\u003c\/strong\u003e\u003cspan class=\"spm-sub\"\u003e(SPM-HEP-4756)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003eCummins 6CT8.3 and 6CT8.3-D diesel engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e3251385\u003c\/strong\u003e\u003cspan class=\"spm-sub\"\u003e(SPM-HEP-4756)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003eCummins 6CT8.3 and 6CT8.3-D diesel engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e3256759\u003c\/strong\u003e\u003cspan class=\"spm-sub\"\u003e(SPM-HEP-4756)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003eCummins 6CT8.3 and 6CT8.3-D diesel engines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch2 class=\"spm-h2\"\u003eApplications \u0026amp; Use Cases\u003c\/h2\u003e\n\u003cp class=\"spm-p\"\u003e\u003cstrong\u003eBattery not charging\u003c\/strong\u003e\u003cbr\u003eA charge warning light or flat batteries every morning point to the alternator once the belt and wiring check out.\u003c\/p\u003e\n\u003cp class=\"spm-p\"\u003e\u003cstrong\u003eNoise\u003c\/strong\u003e\u003cbr\u003eA worn bearing whines or grinds.\u003c\/p\u003e\n\u003cp class=\"spm-p\"\u003e\u003cstrong\u003eLow voltage at idle\u003c\/strong\u003e\u003cbr\u003eWeak output shows as dim lights and slow electrics at idle.\u003c\/p\u003e\n\u003cp class=\"spm-p\"\u003e\u003cstrong\u003eFit with a new belt\u003c\/strong\u003e\u003cbr\u003eChange the belt and check the tensioner when fitting the alternator.\u003c\/p\u003e\n\u003ch2 class=\"spm-h2\"\u003ePrice Beat Guarantee\u003c\/h2\u003e\n\u003c!-- spm-pricebeat --\u003e\u003cp style=\"font-size:15px;line-height:1.8;margin:0 0 16px\"\u003eWe check what other aftermarket sellers charge for this same part. Their prices on the date we checked:\u003c\/p\u003e\n\u003cdiv style=\"overflow-x:auto;margin:0 0 16px\"\u003e\u003ctable style=\"width:100%;border-collapse:collapse;border:1px solid #e2e2e2\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"text-align:left;padding:10px 14px;background:#1a1a1a;color:#fff;font-size:13px;text-transform:uppercase;letter-spacing:.05em\"\u003eSeller\u003c\/th\u003e\n\u003cth style=\"text-align:left;padding:10px 14px;background:#1a1a1a;color:#fff;font-size:13px;text-transform:uppercase;letter-spacing:.05em\"\u003ePrice\u003c\/th\u003e\n\u003cth style=\"text-align:left;padding:10px 14px;background:#1a1a1a;color:#fff;font-size:13px;text-transform:uppercase;letter-spacing:.05em\"\u003eChecked\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px\"\u003eSINOCMP\u003c\/td\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px\"\u003eUSD 299.00\u003c\/td\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px\"\u003e31 Oct 2026\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px\"\u003eeBay, aftermarket seller\u003c\/td\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px\"\u003eUSD 348.00\u003c\/td\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px\"\u003e31 Oct 2026\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px;font-weight:700;background:#fff8d6\"\u003eSpare Part Mart\u003c\/td\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px;font-weight:700;background:#fff8d6\"\u003eUSD 246.97\u003c\/td\u003e\n\u003ctd style=\"padding:10px 14px;border-bottom:1px solid #e2e2e2;font-size:15px;font-weight:700;background:#fff8d6\"\u003eToday\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003c\/div\u003e\n\u003cp style=\"font-size:15px;line-height:1.8;margin:0 0 16px\"\u003eOur price of USD 246.97 is 17% to 29% less than these sellers.\u003c\/p\u003e\n\u003cp style=\"font-size:15px;line-height:1.8;margin:0 0 16px\"\u003eFound this part cheaper somewhere else? Send us the listing and we will beat it by 5% under our \u003ca href=\"\/pages\/find-it-cheaper-we-will-beat-it-by-5\" style=\"color:#000;text-decoration:underline\"\u003ePrice Beat Guarantee\u003c\/a\u003e. Every order is also covered by our \u003ca href=\"\/pages\/30-day-money-back-guarante\" style=\"color:#000;text-decoration:underline\"\u003e30 day money back guarantee\u003c\/a\u003e.\u003c\/p\u003e\n\u003c!-- \/spm-pricebeat --\u003e\u003ch2 style=\"font-family:'Montserrat',sans-serif;font-size:24px;font-weight:900;color:#000;text-transform:uppercase;margin-top:40px;margin-bottom:20px;letter-spacing:.05em;border-bottom:3px solid #ffce02;padding-bottom:15px\"\u003eFrequently asked questions\u003c\/h2\u003e\n\u003cdiv style=\"margin:20px 0\"\u003e\n\u003cdiv style=\"margin-bottom:25px;padding:15px;background:#f9f9f9;border-left:4px solid #ffce02\"\u003e\n\u003ch4 style=\"color:#000;font-weight:700;margin-bottom:10px;font-size:15px\"\u003eWill it fit my Cummins 6CT8.3?\u003c\/h4\u003e\n\u003cp style=\"font-size:14px;line-height:1.7;margin:0;color:#333\"\u003eYes, it was made for the Cummins 6CT8.3, and 1 more listed under compatible equipment. Check the old alternator is marked 3256759 or one of the cross references, because makers change parts between serial ranges.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom:25px;padding:15px;background:#f9f9f9;border-left:4px solid #ffce02\"\u003e\n\u003ch4 style=\"color:#000;font-weight:700;margin-bottom:10px;font-size:15px\"\u003eHow often should I replace the alternator on my Cummins 6CT8.3?\u003c\/h4\u003e\n\u003cp style=\"font-size:14px;line-height:1.7;margin:0;color:#333\"\u003eOn the Cummins 6CT8.3, typically 5,000 to 10,000 hours, depending on how often the machine is started and how well the batteries are kept.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom:25px;padding:15px;background:#f9f9f9;border-left:4px solid #ffce02\"\u003e\n\u003ch4 style=\"color:#000;font-weight:700;margin-bottom:10px;font-size:15px\"\u003eWhat are the signs the alternator needs replacing?\u003c\/h4\u003e\n\u003cp style=\"font-size:14px;line-height:1.7;margin:0;color:#333\"\u003eA charge warning, low battery voltage with the engine running, flickering lights or bearing noise.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom:25px;padding:15px;background:#f9f9f9;border-left:4px solid #ffce02\"\u003e\n\u003ch4 style=\"color:#000;font-weight:700;margin-bottom:10px;font-size:15px\"\u003eDo I need to move the pulley or fan?\u003c\/h4\u003e\n\u003cp style=\"font-size:14px;line-height:1.7;margin:0;color:#333\"\u003eCheck the old unit before you send it away. Pulleys and fans are often fitted to suit the machine and have to be moved across.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom:25px;padding:15px;background:#f9f9f9;border-left:4px solid #ffce02\"\u003e\n\u003ch4 style=\"color:#000;font-weight:700;margin-bottom:10px;font-size:15px\"\u003eWhat should I disconnect first?\u003c\/h4\u003e\n\u003cp style=\"font-size:14px;line-height:1.7;margin:0;color:#333\"\u003eDisconnect the battery earth before removing the old unit. The main cable is live at full battery current.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom:25px;padding:15px;background:#f9f9f9;border-left:4px solid #ffce02\"\u003e\n\u003ch4 style=\"color:#000;font-weight:700;margin-bottom:10px;font-size:15px\"\u003eIs this a genuine Cummins 3256759?\u003c\/h4\u003e\n\u003cp style=\"font-size:14px;line-height:1.7;margin:0;color:#333\"\u003eNo. It is an aftermarket alternator made to replace the Cummins 3256759. It is not made by the original manufacturer; the number only shows what it replaces.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-top:50px;display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:#d1d1d1;border:1px solid #d1d1d1;margin-bottom:20px\" class=\"spm-trust\"\u003e\n\u003ca href=\"\/pages\/30-day-money-back-guarante\" style=\"background:#fff;padding:40px 15px;text-decoration:none;display:flex;flex-direction:column;align-items:center;text-align:center;color:#1a1a1a\"\u003e\u003csvg style=\"width:32px;height:32px;margin-bottom:15px;fill:#ffce02\" viewbox=\"0 0 24 24\"\u003e\u003cpath d=\"M12 1L3 5v6c0 5.55 3.84 10.74 9 12 5.16-1.26 9-6.45 9-12V5l-9-4zm-2 16l-4-4 1.41-1.41L10 14.17l6.59-6.59L18 9l-8 8z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\u003cspan style=\"font-family:'Roboto Condensed',sans-serif;font-weight:700;text-transform:uppercase;font-size:11px;letter-spacing:0.1em\"\u003e30-Day Money Back Guarantee\u003c\/span\u003e\u003c\/a\u003e\u003ca href=\"\/pages\/delivery-information\" style=\"background:#fff;padding:40px 15px;text-decoration:none;display:flex;flex-direction:column;align-items:center;text-align:center;color:#1a1a1a\"\u003e\u003csvg style=\"width:32px;height:32px;margin-bottom:15px;fill:#ffce02\" viewbox=\"0 0 24 24\"\u003e\u003cpath d=\"M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm-1 17.93c-3.95-.49-7-3.85-7-7.93 0-.62.08-1.21.21-1.79L9 15v1c0 1.1.9 2 2 2v1.93zm6.9-2.54c-.26-.81-1-1.39-1.9-1.39h-1v-3c0-.55-.45-1-1-1H8v-2h2c.55 0 1-.45 1-1V7h2c1.1 0 2-.9 2-2v-.41c2.93 1.19 5 4.06 5 7.41 0 2.08-.8 3.97-2.1 5.39z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\u003cspan style=\"font-family:'Roboto Condensed',sans-serif;font-weight:700;text-transform:uppercase;font-size:11px;letter-spacing:0.1em\"\u003eWorldwide Delivery\u003c\/span\u003e\u003c\/a\u003e\u003ca href=\"\/pages\/find-it-cheaper-we-will-beat-it-by-5\" style=\"background:#fff;padding:40px 15px;text-decoration:none;display:flex;flex-direction:column;align-items:center;text-align:center;color:#1a1a1a\"\u003e\u003csvg style=\"width:32px;height:32px;margin-bottom:15px;fill:#ffce02\" viewbox=\"0 0 24 24\"\u003e\u003cpath d=\"M21.41 11.58l-9-9C12.05 2.22 11.55 2 11 2H4c-1.1 0-2 .9-2 2v7c0 .55.22 1.05.59 1.42l9 9c.36.36.86.58 1.41.58.55 0 1.05-.22 1.41-.59l7-7c.37-.36.59-.86.59-1.41 0-.55-.23-1.06-.59-1.42zM5.5 8.25c-.69 0-1.25-.56-1.25-1.25s.56-1.25 1.25-1.25 1.25.56 1.25 1.25-.56 1.25-1.25 1.25z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\u003cspan style=\"font-family:'Roboto Condensed',sans-serif;font-weight:700;text-transform:uppercase;font-size:11px;letter-spacing:0.1em\"\u003ePrice Beat Guarantee\u003c\/span\u003e\u003c\/a\u003e\n\u003c\/div\u003e\n\n\u003c\/div\u003e\u003cscript type=\"application\/ld+json\"\u003e{\"@context\": \"https:\/\/schema.org\", \"@graph\": [{\"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"Will it fit my Cummins 6CT8.3?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Yes, it was made for the Cummins 6CT8.3, and 1 more listed under compatible equipment. Check the old alternator is marked 3256759 or one of the cross references, because makers change parts between serial ranges.\"}}, {\"@type\": \"Question\", \"name\": \"How often should I replace the alternator on my Cummins 6CT8.3?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"On the Cummins 6CT8.3, typically 5,000 to 10,000 hours, depending on how often the machine is started and how well the batteries are kept.\"}}, {\"@type\": \"Question\", \"name\": \"What are the signs the alternator needs replacing?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"A charge warning, low battery voltage with the engine running, flickering lights or bearing noise.\"}}, {\"@type\": \"Question\", \"name\": \"Do I need to move the pulley or fan?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Check the old unit before you send it away. Pulleys and fans are often fitted to suit the machine and have to be moved across.\"}}, {\"@type\": \"Question\", \"name\": \"What should I disconnect first?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Disconnect the battery earth before removing the old unit. The main cable is live at full battery current.\"}}, {\"@type\": \"Question\", \"name\": \"Is this a genuine Cummins 3256759?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"No. It is an aftermarket alternator made to replace the Cummins 3256759. It is not made by the original manufacturer; the number only shows what it replaces.\"}}]}]}\u003c\/script\u003e","brand":"Spare Part Mart","offers":[{"title":"Default Title","offer_id":67724874842412,"sku":"SPM-HEP-4756-P1","price":246.97,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0715\/9152\/6700\/files\/sino46_3964745_0.jpg?v=1793444002","url":"https:\/\/sparepartmart.co\/products\/cummins-3256759-aftermarket-alternator","provider":"Spare Part Mart","version":"1.0","type":"link"}