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Cummins 4946255 is the 24 volt 70 amp alternator: the ribbed housing with the poly V pulley, the mounting ears and the rear cover with the B+ terminal and plug. It is used on Cummins ISLe, 6C8.3, ISL9.5 and L8.9 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.
Sold as one unit. Check the number on your old part, or in the parts manual for your machine, before ordering.
| Part Type | Alternator |
| Replaces | Cummins 4946255 |
| Voltage | 24 V |
| Output | 70 A |
| Engine | Cummins ISLe, 6C8.3, ISL9.5, L8.9 |
| Fits | machines, trucks and gen sets with the Cummins ISLe, 6C8.3, ISL9.5 and L8.9 engines |
| Condition | New, aftermarket |
| Stat. HS-Code | 851150 |
| Country of Manufacture | China |
Machines
Check the part number on your old unit before ordering.
| Cummins Part No.(SPM Part No.) | Fits |
|---|---|
| 4946255(SPM-HEP-5227) | machines, trucks and gen sets with the Cummins ISLe, 6C8.3, ISL9.5 and L8.9 engines |
Battery not charging
A charge warning light or flat batteries every morning point to the alternator once the belt and wiring check out.
Noise
A worn bearing whines or grinds.
Low voltage at idle
Weak output shows as dim lights and slow electrics at idle.
Fit with a new belt
Change the belt and check the tensioner when fitting the alternator.
We check what other aftermarket sellers charge for this same part. Their prices on the date we checked:
| Seller | Price | Checked |
|---|---|---|
| Fab Heavy Parts | USD 295.12 | 3 Nov 2026 |
| Kudu Parts | USD 299.00 | 3 Nov 2026 |
| SINOCMP | USD 319.00 | 3 Nov 2026 |
| FridayParts | USD 324.45 | 3 Nov 2026 |
| eBay, aftermarket seller | USD 385.00 | 3 Nov 2026 |
| Spare Part Mart | USD 242.39 | Today |
Our price of USD 242.39 is 18% to 37% less than these sellers.
Found this part cheaper somewhere else? Send us the listing and we will beat it by 5% under our Price Beat Guarantee. Every order is also covered by our 30 day money back guarantee.
Yes, it is a direct replacement for the Cummins 4946255 with the same fitting.
Typically 5,000 to 10,000 hours, depending on how often the machine is started and how well the batteries are kept.
A charge warning, low battery voltage with the engine running, flickering lights or bearing noise.
Disconnect the battery earth before removing the old unit. The main cable is live at full battery current.
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.
No. It is an aftermarket alternator made to replace the Cummins 4946255. It is not made by the original manufacturer; the number only shows what it replaces.
Live rates for the quantity selected, delivered to your door. Confirmed at checkout.
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Join Marty Mates and we put 200 points on your account, worth $10 off an order over $75 USD. Then a point for every dollar you spend after that.
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