unknown model/proper transmission fluid?

[klide72 0]

I have a Wheel Horse that has a serial number plate stating:01 12KS01 03879, with 7354 stamped below this. It has a K321 Koehler engine (that's what someone scratched into it). It's around 30 years old. When I mow for 45 mins or so, the transmission starts slipping, and sometimes takes 15-30 seconds to move when I switch from forward to reverse. What transmission fluid do I need? What model tractor is this? Is the old transmission fluid/filter likely the problem? Thanks for any help!

[TT-(Moderator) 1,147]

:D

Your tractor would be an early 1980 C-125 automatic.

The original engine would have been a 12hp K301AS Kohler single and the transmission would take 10W-30 or 10W-40 "motor oil".

A fluid & filter change would be a good place to start, but not necessarily a cure for an "old" Sundstrand hydro unit. Keep your fingers crossed! :USA:

[rmaynard 15,892]

:D

Glad to have you aboard.

Bob

[rickv1957 73]

Hello and Rick

[Duff 206]

:USA:, and good luck! Somebody's always around here to help!

Duff :D

[SMITTY 23]

After reading the reply about using 10 w30 or 10w 40 my owners manual says use type a trans fluid. I changed to using dextron. Would you suggest changing to motor oil?

[TT-(Moderator) 1,147]

After reading the reply about using 10 w30 or 10w 40 my owners manual says use type a trans fluid. I changed to using dextron. Would you suggest changing to motor oil?

If your tractor was manufactured before mid-1973 and has the Sundstrand Hydrogear unit, it would have originally used type "A" ATF.

Tractors built from mid-1973 up to mid 1980 that used a Sundstrand piston-to-piston unit take 10W-30 / 10W-40 motor oil.

Although the early units will function fine with motor oil, it is important to purge the system of ATF (as much as possible) when changing over.

[piecrazy4 0]

:D