Operating weight should be about 28,000-29,000 pounds. Engine would be a 3304 and about 130HP. I guess the major weak point in my opinion is the air over hydraulic brake system. Also, a lot of these loaders are old enough now that if the air system hasn't been kept up, then there will be some issues showing up with that. I know the two major problems we usually have with our 81J is the brake system and the air system. Someone can correct me if I'm wrong, but I believe 58H was the first prefix built in Canada. I think Canada started production of 950s in 1965 so I would imagine yours is a year or two newer than that.