Is anyone familiar with a Hogzilla tub grinder. It's for grindig big logs and stumps into mulch. You have the option when you buy one of either having a PTO, fluid coupler, or torque converter to turn the tub/grinder. Powered by @1000 horsepower diesel engine.These monsters cost in the neighborhood of $500,000. The torque converter is made by "Twin Disk". My question is, the converter uses Delvac 1210, which is a non- detergent 10W diesel engine oil(as far as i can tell).... Why a 10w(single weight)? Why non-detergent?Why not an ATF type oil? Why not synthetic...due to the fact that it's used in the dead of winter as well as the hot of summer and with extreme loading? I'm sure Twin Disk knows what there doing, but why their choice of delvac 1210?