Cat C-7 diesel oil viscosity
I have a 2004 Cat C-7 in a 36' Meridian which I have been using Rotella 15W-40 oil in it since new 68,000 miles back. Seems I remember reading somewhere the thought was that 10W-30 was better for the...
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I think I know what 5W, 10W, and 15W would indicate as the first set of numbers in oil weight but what does 0W mean where the viscosity of oil is concerned?
I guess I started using 15W-40 since the recommendation by Cat is 10W-30 if the ambient temperature if 104 or less and 15W-40 if temps goes up to 122 degrees. With the screwy summer temperatures here in Oklahoma and Kansas sometimes can reach 104 or higher I always figured the 10W-30 might be right at the top of the ambient temperatures in the summer. We never have driven in temperatures lower than 30-35 and if the morning start-up temps are ever projected to be lower than 50 I always run the engine heater for several hours first.
I guess I started using 15W-40 since the recommendation by Cat is 10W-30 if the ambient temperature if 104 or less and 15W-40 if temps goes up to 122 degrees. With the screwy summer temperatures here in Oklahoma and Kansas sometimes can reach 104 or higher I always figured the 10W-30 might be right at the top of the ambient temperatures in the summer. We never have driven in temperatures lower than 30-35 and if the morning start-up temps are ever projected to be lower than 50 I always run the engine heater for several hours first.
