Oil Recommendations for Sovereign 18

[U.S. Vintage Iron]

Ok more questions for you simplicity experts   
 

1.Besides the engine,BGB, and hydrostatic transmission, is there anything else that requires oil on this machine? I.e. deck lift or differential 

2. What oil do you guys recommend? 

3. Anybody know the filter number for the trans?

 

My model number is 1692796. Not sure of the year but I think 96-97

[rbstuartjr]

On that Sovereign the BGB and rear end take the same hydraulic fluid. I use tractor supply premium hydraulic fluid, which is compatible according to Sundstrand. For hydro filter, I use Wix 51307. I believe the oem is 1709322sm.. The hydraulic lift and differential uses the fluid in the common sump for the hydraulic system. I changed the hydraulic fluid and filters when I first got my Sovereigns, because it was unknown how old the fluid was. It was probably fine but I changed it for piece of mind.

For the engine oil, I’m using synthetic Mobile 1 10w-30 and a Wix filter as well. I’m sure any 10w-30 would be fine as long as it is changed regularly. I usually just change it once a year but could probably go longer.

[U.S. Vintage Iron]

54 minutes ago, rbstuartjr said:

On that Sovereign the BGB and rear end take the same hydraulic fluid. I use tractor supply premium hydraulic fluid, which is compatible according to Sundstrand. For hydro filter, I use Wix 51307. I believe the oem is 1709322sm.. The hydraulic lift and differential uses the fluid in the common sump for the hydraulic system. I changed the hydraulic fluid and filters when I first got my Sovereigns, because it was unknown how old the fluid was. It was probably fine but I changed it for piece of mind.

For the engine oil, I’m using synthetic Mobile 1 10w-30 and a Wix filter as well. I’m sure any 10w-30 would be fine as long as it is changed regularly. I usually just change it once a year but could probably go longer.

Ok. Thanks for the info. I definitely want to change my hydro fluid because the guy I bought it from replaced a line that was leaking and topped off with ATF so I’m going to replace it and change the filter. 
 

Thanks for helping me out

[PhanDad]

I agree pretty much with what @rbstuartjr said above.  

However, I don't like mixing fluids so IMO,  it's always best to try and figure out what's in the machine already.  If it's different from what you want to use, then several drain/fill/run/ cycles are necessary to get all the "wrong" fluid out, especially the hydro/hydro lift system since there' a lot of "piping" and the lift cylinder volume that doesn't completely drain.  For the BGB, some prefer to run 90wt gear oil (old spec).  If you do a search for hydro fluids, you'll get many hits.  The "official" Simplicity fluid  recommendations can be found at this link (FAQ):

https://simpletractors.com/forums/topic/41614-transmission-gearbox-lubrication-charts/

 

As to your Command Engine, here is the Kohler recommendations (from the 2008 Owners Manual:

I also use synthetic oil in my Command, 10W-30 Mobil 1.  I don't think switching from a dinosaur based oil to synthetic is an issue.  

 The tractor operator manual shows grease points and steps to change the BGB and Tranny Fluid.  IMO it's worth reading some of the posts about changing the Tranny Fluid in addition to the manual steps.  As to the BGB, the newer tractors no longer have a drain plug; the instructions state to loosen the cover bolts and drain - but usually the gasket holds the cover on and it won't drain.  Then you pry at the bottom of the cover and mess up the gasket and then it won't seal.  So many of us use a "turkey baster" with a tubing extension (or something similar) to suck the old fluid out (then a fill/run/repeat cycle). There are posts about that as well.  

 

[U.S. Vintage Iron]

Pretty sure the guy I bought it from just used dex merc atf so I will definitely drain and fill a couple times. I do know it was not ran much with the fluid mixed because he replaced a line and topped it off right before I bought it. I will also pump out the BGB so as not to disturb the gasket. Thank you