The three transmissions were reverser, with lever on left side of steering wheel to switch from forward to reverse without clutching, a Hi-Lo with left lever that has a two speed in each gear to give you 16 forward gear ratios instead of 8. The standard transmission if before serial number 340,000 is a collarshift which is non-synchronized and if above 340,000 the standard transmission is TSS which the right side shift lever for gears 1-4 is synchronized. For loader work the reverser is a great transmission, but for row crop work or baling, the hi-lo is nice for the extra gear ratios.
It would be interesting to find out exactly what kind of synthetic oil as used that caused the pump failures. I would not think synthetic oil should hurt the brakes, but bad brakes can hurt the pumps. Bad brakes don't usually give obvious signs they are bad. Usually first signs are slow hydraulics from filters getting clogged with brake material and/or metal filings. Brake performance many times is still good. Sometimes the pedal can get spongy, but spongy brakes may just mean there is air in the system and needs to be bled out. Most important with brakes is to prevent water contamination in the oil. If oil looks milky, beware there is high likelihood of brake problems.