Cummins/Onan — Crankcase Oil Change
Maintenance · Lubrication system
From a Cummins/Onan operator's manual covering: 12.0 DJC, 4.5 DJB, 4.5 DJE, 6.0 DJB, 6.0 DJE, 9.0 DJC. Check it applies to your exact model before use.
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Before you start
- Hot crankcase oil can cause burns if spilled or splashed on skin
Procedure
- Stop engine and drain crankcase oil while still hot
- Place pan under drain outlet and remove oil drain plug or open drain valve
- After completely drained, replace drain plug or close drain valve
- Replace oil filter if necessary before adding oil
- Refill with oil of correct API designation and SAE viscosity grade
Specs & values
- Oil capacity per Specifications section
Source: Cummins/Onan operator's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.