the old grind
Super Member
- Joined
- Jul 21, 2012
- Messages
- 5,308
- Location
- Mid-Michigan
- Tractor
- NH T-1520 HST, NH TC33DA HST, Case DX26 HST, .Terramite T5C, . NH L785
I agree with 15w-40 motor oil as a sub for most hydraulic if not with HST, but including in oldies that spec'd 30w.
Additive differences or compromises are minimized when realistic change intervals and levels are maintained, IME moot whether or not.
btw, My current and last ZTRs and Terramite call out 15w-40 diesel motor oil, and the T5C does include the HST drive-motor, so what do I know.
The best way to park, if not also to measure hydro level per OM, is with all cylinders collapsed. This will minimize airspace, 'breathing' with temp/humidity changes, thermal expansion, condensation, and/or damp air intrusion as cyls 'settle'. You knew that.
No matter what we change or flush with, there will be some dilution. Don't ever sweat that. Be wary of ATF. Its low surface tension (film strength, lubricity) is ok with vane-type pumps but not so good for hydro systems.
Additive differences or compromises are minimized when realistic change intervals and levels are maintained, IME moot whether or not.
btw, My current and last ZTRs and Terramite call out 15w-40 diesel motor oil, and the T5C does include the HST drive-motor, so what do I know.
The best way to park, if not also to measure hydro level per OM, is with all cylinders collapsed. This will minimize airspace, 'breathing' with temp/humidity changes, thermal expansion, condensation, and/or damp air intrusion as cyls 'settle'. You knew that.
No matter what we change or flush with, there will be some dilution. Don't ever sweat that. Be wary of ATF. Its low surface tension (film strength, lubricity) is ok with vane-type pumps but not so good for hydro systems.
