On Dec 11, 9:14 am, "Harry K" wrote:
... been kicking
myself ever since for not going the extra cost for hydro. I have never
heard of anyone having a problem with them in cold weather.

It is true. When I got my tractor (cold, snowy winter of 95-96) it
would hardly move at all the first time I tried to use it. The temp
was below 0. I called and complained and the manufacturer explained
that the oil in the drive wasn't meant for below 0 operation and that
it needed to be replaced. Even after replacement it has to warm up for
a while when the outside temps are low before it will operate properly
against resistance (going uphill or pushing into a thick snow). Works
fine in warmer temps and once it has warmed up.

By the way, replacing oil like that when it is below zero is an
interesting experience.

On heavy duty equipment they put heaters on the hydrostatic drive
system. There are even patents for this kind of thing. For instance:

http://www.freepatentsonline.com/4624333.html