3205 power steering "slop" when cold
 

My 3205's steering has about a 1/4 turn of slack where the steering wheel doesn't move the tires when just starting the unit. After about 5-10 minutes of mowing, it returns to normal. Could this be air in the system, or does the steering unit need a rebuild?

It's a hydrostatic power steering system. No positive connection between the steering wheel and the wheels. If it only does it during warm up, it's probably not wore out. Hydrostatic power steering systems tend to have issues when they are hot when they are worn out.

My suggestion: change the fluid and filter on the rear, and let it warm up a few minutes before mowing.

I'll mirror what Jon says, and add:
You could have air in the system from starvation/cavitation .
It sounds like you are not able get enough flow/pressure in your system till warm, caused by dirty filter and/or contaminated fluid.
That condition will cause noise and jerkiness also.
Your tractor is 20 years old, it prolly has not had the hydraulic oil & filter replaced.:bigthink:

I just had the differential out to tighten the bolts holding the diff together and to replace the seals. A new cub cadet filter and tractor/hydraulic oil was installed. The steering was doing this before the repair, though.