We describe the laser performance and thermal properties of side-pumped Nd:YAG rod lasers that use fiber-coupled diode lasers as pump sources. Utilizing a nearly homogeneous pump light profile, we realize an output power of more than 60 W in TEM00 mode operation with optical-to-optical efficiencies of more than 25\%. In multimode operation, optical slope efficiencies of more than 46\% are observed.