The present invention relates to an extra light hydrocarbon liquid derived from highly paraffinic wax. This extra light hydrocarbon liquid is suitable for use as a lubricant additive diluent oil in oil soluble additive concentrates. This extra light hydrocarbon liquid derived from highly paraffinic wax has a viscosity of between about 1.0 and 3.5 cSt at 100° C. and a Noack volatility of less than 50 weight % and comprises greater than 3 weight % molecules with cycloparaffinic functionality and less than 0.30 weight percent aromatics. The extra light hydrocarbon liquid makes an excellent lubricant additive diluent oil because it has low volatility, low viscosity, good additive solubility, and excellent solubility in lubricant base oil stocks. The present invention also relates to finished lubricants comprising the oil soluble additive concentrates made with the extra light hydrocarbon liquid and finished lubricants comprising the oil soluble additive concentrates. The present invention further relates to processes for making these lubricant additive diluent oils, oil soluble additive concentrates, and finished lubricants.