Diol 9 RD 40

Railroad Crankcase Oils

DIOL™ 9 RD series oils are premium heavy-duty crankcase lubricants for locomotive diesel engines. These products are designed to meet the severe service demands imposed by the latest railroad diesel locomotive engines. An Electro-Motive Diesel (EMD) and General Electric (GE) endorsed additive system provides excellent engine protection, oil consumption control and oil drain interval extension capability.


Equipment lubricant recommendations

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Data sheets

Features and Benefits

•  Zinc Free - Excellent Silver Bearing Lubricity

•  Enhanced Oxidation, Sludge-Soot Handling and Viscosity Control

•  Excellent Deposit, Corrosion and Wear Control

•  Formulated for use with low sulfur and ultra-low sulfur diesel fuels

•  Extended oil drain intervals and high locomotive utilization rates

•  Chlorine Free



DIOL 9 RD oils are formulated to an LMOA Generation 5 quality level with an engine manufacturer endorsed additive package. They meet the requirements of for all EMD and General Electric diesel locomotives.


The newest improvements in General Electric and EMD engines are modified piston rings and cylinder liners that have significantly reduced oil consumption. This drastic reduction in the amount of fresh oil makeup, plus the higher operating temperatures of the newer engines, places an extra burden on the oil. The good base number retention and improved oxidation inhibition of DIOL railroad oils provide excellent service under these conditions, even with extended oil drain intervals.


Specifications and Approvals


This product has the following approvals:

9 RD 40

DIOL 9 RD 20W-40

EMD Domestic Common Additive Approach (recognition ltr on file)



GE Transportation, A Wabtec Company LMOA Gen 4 LL - Fundamental Approval (letter on file)




This product meets or exceeds the requirements of:

9 RD 40


EMD Domestic Common Additive Approach (recognition ltr on file)



GE Gen 4 LL - Fundamental Approval (letter on file)




Properties and Specifications


9 RD 40

DIOL 9 RD 20W-40


SAE 40

SAE 20W-40

Flash Point, °C, ASTM D92



Kinematic Viscosity @ 100 C, mm2/s, ASTM D445



Kinematic Viscosity @ 40 C, mm2/s, ASTM D445



Pour Point, °C, ASTM D97



Total Base Number, mgKOH/g, ASTM D2896



Viscosity Index, ASTM D2270



Zinc, mg/kg, ASTM D5185




Health and Safety

Health and Safety recommendations for this product can be found on the Material Safety Data Sheet (MSDS) @ http://www.msds.exxonmobil.com/psims/psims.aspx