Genuine Green Label spin-on oil filter with bypass valve for QD and HQD Series Quiet Diesel generators. Replace every 150 hours.
The Cummins Onan 122-0833 is the OEM-specified spin-on oil filter for the HDKAH, HDKAJ, HDKAK, and HDKBA Quiet Diesel (QD Series) generators and the HQDPA and HQDPC High-powered Quiet Diesel (HQD Series). It supersedes earlier part numbers 185-5801 and 185-5409.
The filter features an integrated bypass valve that allows oil to flow during cold starts or if the element becomes restricted. Aftermarket "will-fit" filters frequently lack bypass valves — as they trap debris, oil pressure starvation can occur, leading to elevated pressures, failed gaskets, and engine damage. On a diesel engine operating under higher compression and thermal load, this risk is amplified.
This filter is also available as Fleetguard LF3591 — a Cummins-owned filtration brand and direct OEM equivalent.
Integrated bypass valve prevents oil starvation during cold starts and filter restriction — non-bypass filters cause elevated pressure, failed gaskets, and engine damage
Current part 122-0833 replaces both earlier numbers — if your service records show either old number, this is the correct current filter
Fleetguard LF3591 is a direct Cummins OEM substitute — identical specifications; you may receive either label
Tested and designed specifically for Cummins Onan QD and HQD Series Quiet Diesel RV generators — meets original lubrication specifications
This filter fits the HDKAH/HDKAJ/HDKAK (all spec letters through L), HDKBA, HQDPA, and HQDPC only. Other Cummins Onan diesel generator families use different oil filters: • HDKCA / HDKCB / HDKLA / HDKLB — use 122-0893 • HDCAA / HDCAB — use 187-1000 • HDKAG / HQDPB — use 185-5835 • DKC RV / DKD RV / DKG — use 122-0827 Always confirm the generator model series from the identification nameplate — wattage alone is not sufficient.
Fleetguard is Cummins' own filtration brand. The LF3591 is not an aftermarket substitute — it is a Cummins OEM product with identical specifications to the 122-0833. If you receive a Fleetguard LF3591 in place of the Onan-labeled 122-0833, this is a genuine direct substitute and will not affect performance or warranty standing.
Backed by a 90-day limited manufacturer's warranty against defects in materials and workmanship. Cummins Power Generation warrants only the quality and integrity of Green Label Parts. Damage caused by the use of non-Green Label or non-bypass oil filters is not covered under the Cummins Onan limited warranty.