hello, I'm new the the forums. I bought a 542b not long ago and when i was moving snow the other day it started viberatiing and making a grinding noise only when i try to going in revorse with the left side and then losing power if i go forward at full speed, i thought it might be a U joint going out but today when i went out to take a look at it there was hydraulic oil on the floor on the back left side and it looked like it was coming out of the hydraulic control valve. my question is where do i start to look. thanks