Overview – HUB, TIMING 3256855 Series
3256855 is the CUMMINS part number for this HUB, TIMING, fitted in Cummins diesel engine timing drive applications. We keep the series in our catalogue and can quote it with or without related parts.
Parts Characteristics
3256855 is the CUMMINS timing hub that carries the timing gear drive on the engine, machined to the original bore, keyway and flange dimensions so it locates the gear squarely on the shaft. The hub is manufactured to the OEM material specification with the original heat treatment, giving the wear resistance needed in the timing drive. The bolt pattern matches the original gear, so the assembly installs with the factory hardware.
Applicable Models & Applications
This timing hub is used on CUMMINS diesel engines where the original 3256855 timing drive layout applies, including the engine families that share the timing gear configuration. Confirm the shaft diameter, the keyway and the gear bolt pattern against the hub removed from your engine before ordering. The related 3804993 covers the other variant in the series, and we can confirm the correct hub from your engine serial.
Maintenance & Replacement
Check the hub bore and keyway for wear when the timing gear is removed, as a loose fit on the shaft shifts the timing. Tighten the hub bolts to the specified torque in the correct sequence and re-check the timing marks after assembly. Inspect the key and the mating shaft keyway for fretting, and replace both together if the fit is loose.
Price Reference (USD)
Expect to pay roughly USD 90 – 280 for HUB, TIMING (3256855). Bulk orders and repeat customers receive better rates; final pricing is confirmed by our sales team together with stock availability.
Value & Service
We match 3256855 against the original CUMMINS bore and keyway specification before dispatch, and confirm the correct variant for your engine from the serial. The hub is held in stock together with 3804993, so a timing drive repair is not held up by the part. Our team can also advise on the matching timing gear and key for a complete drive set.
Related part numbers in the HUB, TIMING Series Series: 3804993.
Racer Machinery keeps HUB, TIMING (3256855) and the full CUMMINS range in its catalogue. Send us the machine serial number or the part number, and we will confirm fitment, price and delivery for your order.







