All you need is a decent quality diesel engine oil,
CJ-4 Current For high-speed four-stroke cycle diesel engines designed to meet 2010 model year on-highway and Tier 4 nonroad
exhaust emission standards as well as for previous model year diesel engines. These oils are formulated for use in all
applications with diesel fuels ranging in sulfur content up to 500 ppm (0.05% by weight). However, the use of these oils
with greater than 15 ppm (0.0015% by weight) sulfur fuel may impact exhaust aftertreatment system durability and/or
drain interval. CJ-4 oils are especially effective at sustaining emission control system durability where particulate filters
and other advanced aftertreatment systems are used. Optimum protection is provided for control of catalyst poisoning,
particulate filter blocking, engine wear, piston deposits, low- and high-temperature stability, soot handling properties,
oxidative thickening, foaming, and viscosity loss due to shear. API CJ-4 oils exceed the performance criteria of API CI-4
with CI-4 PLUS, CI-4, CH-4, CG-4 and CF-4 and can effectively lubricate engines calling for those API Service Categories.
When using CJ-4 oil with higher than 15 ppm sulfur fuel, consult the engine manufacturer for service interval.
CI-4 Current Introduced in 2002. For high-speed, four-stroke engines designed to meet 2004 exhaust emission standards implemented
in 2002. CI-4 oils are formulated to sustain engine durability where exhaust gas recirculation (EGR) is used and are
intended for use with diesel fuels ranging in sulfur content up to 0.5% weight. Can be used in place of CD, CE, CF-4,
CG-4, and CH-4 oils. Some CI-4 oils may also qualify for the CI-4 PLUS designation.
CH-4 Current Introduced in 1998. For high-speed, four-stroke engines designed to meet 1998 exhaust emission standards. CH-4 oils
are specifically compounded for use with diesel fuels ranging in sulfur content up to 0.5% weight. Can be used in place
of CD, CE, CF-4, and CG-4 oils.
CG-4 Obsolete OBSOLETE: Introduced in 1995. For severe duty, high-speed, four-stroke engines using fuel with less than 0.5% weight
sulfur. CG-4 oils are required for engines meeting 1994 emission standards. Can be used in place of CD, CE,
and CF-4 oils.
CF-4 Obsolete OBSOLETE: Introduced in 1990. For high-speed, four-stroke, naturally aspirated and turbocharged engines. Can be used
in place of CD and CE oils.
Information from;
So most any oil meeting or exceeding the CH-4 oil spec in the weight that you choose;
10W-30, 10W-40 are popular, I prefer 15W-40 for summer use or
just go with a synthetic 5W-40 year round.