Hydrostatic Transmission Fluid

[rclint]

I have a Craftsman DYT 4000 with hydrostatic transmission with the unit never been serviced... However overall hours on the mower is low as well around 100 hours (with 10 or so of them maybe more being from switch being left on). I have read over post on servicing the "non service" transmission my question is what fluid to use ? I would love to hear from those that have done this, and also what fluid you used.. I would love to be able to get this local off the shelf..

I do have a 5 gallon bucket of Hy-Tran which is supposed to be outstanding fluid I use in my IH Cub Cadet Sundstrand transmission/pump & rearend

 

[JTK]

Your DYT 4000 most likely has a Hydrogear brand hydrostatic drive. If you do dump and fill it, you will want to refill with a quality 20w50 motor oil.

Joel

 

[gd9704]

I used Mobil 1 extended performance 5w-50 in my tuff torq k51 and for a 2+ years has been A-1.

 

[sweezy722]

If the unit has a tag on it saying hydrogear then JTK is correct. The service department at hydrogear is very friendly and told me 2 years ago that plain 20-50 motor oil is all you need to refill with. He told me that they had 2 models that used something different but they were something out of the ordinary.

If it is a tuff torq unit then it most likely will take 10-30 motor oil.

 

[rclint]

Thanks for the info, I will check the tag for sure before changing the fluid..

 

[motorcity]

They are real easy to service. Theirs a black cap on top. just pry it off, and remove the magnet under it. And then turn the axle over on a drain pan to drain. When you are re-filling it, turn the fan and axle shafts, this helps bleed the air out of the internal pump.When your done putting the axle back in, its a good idea to run the tractor , with the rear wheels up in the air. this makes sure the system is bled of air.

 

[rclint]

uhgg motorcity that sounds pretty involved !! You have to remove the axle from the tractor in order to do a fluid change ?

What is your opinion on the fluid, does it extend the life of the rear axle/pump when changing the fluid ?

 

[JTK]

Originally Posted By: rclint
uhgg motorcity that sounds pretty involved !! You have to remove the axle from the tractor in order to do a fluid change ?

What is your opinion on the fluid, does it extend the life of the rear axle/pump when changing the fluid ?


It's not as bad as it sounds. Parking brake linkage, motion control linkage, drive belt and 4-6 bolts and it's off. Fresh clean oil in there can only help these units. The main thing for longevity is, keep the unit clean and dry and make sure the cooling fan is intact. I've seen badly neglected hydrostatic trans come back to life after an oil change.

Joel

 

[motorcity]

Originally Posted By: JTK
Originally Posted By: rclint
uhgg motorcity that sounds pretty involved !! You have to remove the axle from the tractor in order to do a fluid change ?

What is your opinion on the fluid, does it extend the life of the rear axle/pump when changing the fluid ?


It's not as bad as it sounds. Parking brake linkage, motion control linkage, drive belt and 4-6 bolts and it's off. Fresh clean oil in there can only help these units. The main thing for longevity is, keep the unit clean and dry and make sure the cooling fan is intact. I've seen badly neglected hydrostatic trans come back to life after an oil change.

Joel


I have to agree, if you have a hilly yard to cut, I think the preventitive maintanence is a good measure. taking it out for the first time is a little bit of a pain. But i can have an axle out of a Cub Cadet in about 30 min. It helps if you have some help putting it back in, they need to guide the control rods in as you get the axle in position to raise back up.

 

[JTK]

Originally Posted By: motorcity
...It helps if you have some help putting it back in, they need to guide the control rods in as you get the axle in position to raise back up.



Good plan right there mc. They can be a PITA to fiddle into place later on.

Joel

 

[motorcity]

One other trick I do, is I put hairpin type clips back on, instead of cotter pins. It makes it alot easier next time.Some of the cotter pins can be a real pain to get out and back in. Due to their location, and sppace around them to try and bend them over and straiten them out.

 

[AlanJW]

I have a tuff torq tranny in my john deer, they told me to use 10w30? is that right, some of the other guys said 20w 50? I made the mistake of trying to use gear oil the first time.

 

[Brett Miller]

I put Syntec 5W-50 in my K46 Tuff Torq.

 

[motorcity]

The Tuff torq's us a lighter oil than the Hydro gears. 20w-50 for Hydro Gear and 10w-30 in the Tuff Torqs. I put Amsoil Tractor Hydrualic Fluid in a Tuff Torq, with good results

 

[AlanJW]

ok, thanks, I still probably need to change the fluid again, not to sure I got all the gear oil out, Its Kinda sluggish when I start out in colder temps, but as i get gowing, it smoothes out

 

[JTK]

Yes, I'm not sure what's so different to the internals to a Tufftorq trans over a Hydrogear where TT specs 10w30 over 20w50. I have read where owners of well used TT's refilled with 20w50 with good results.

Joel

 

[Brett Miller]

Originally Posted By: JTK
Yes, I'm not sure what's so different to the internals to a Tufftorq trans over a Hydrogear where TT specs 10w30 over 20w50. I have read where owners of well used TT's refilled with 20w50 with good results.

Joel


Tuff Torq recommends 5W-50 synthetic oil as service fill for many of their transmissions.

 

[M Smith]

Mobil markets a 5W-50?

 

[M Smith]

What have you guys got to say about substituting Amsoil MCV, 20W-50 motorcycle oil, for any 5W-50 motor oil that may be available on the retail market? I’ve got a Tuff Torq T-40 Hydro-Automatic transmission in my John Deere lawn tractor. The unit comes filled with 10W-30, though Tuff Torq recommends replacing that with a 5W-50 synthetic oil meeting API CD.

 

[JTK]

I'd say it's a great choice. Given they only hold a quart or two. I'd want the best in there.

Joel