Amsoil Synthetic Tractor Hydraulic/Transmission Oil SAE 5W-30

[oldnslo]

I just noticed today that my tc18 has a loud whining when I peddle forward or backwards. My fluids are good topped off. Doesn't whine using the bucket or blower. Just when I use my hydrostatic peddle for forward/backwards. Suggestions......pls...... don't want to hurt anything. Gets louder as my rpms go up.

Is it a whine or more of a chattering growling noise? If a whine this is somewhat common on HST since you have pistons moving and parts spinning. Some tractors are worse than others. Does the noise change as the oil warms up?

Chattering growling type noise is potentially cavitation caused by cold oil and this will destroy hydraulic systems. Normally this sounds more like a rock crusher Vs a whine so it usually a very obvious difference.