L4240 GST 1,000 Hour Service

   / L4240 GST 1,000 Hour Service #11  
Last February, I purchased a L3940 GST. First thing I did was replaced all the fluids. If you are doing that yourself, I would encourage you to youtube how to change them prior to performing the tasks. Definitely, when changing the fuel filter.
   / L4240 GST 1,000 Hour Service
  • Thread Starter
Been reading through the WSM and ordering filters and fluids.

Can I expect to drain the full 11.4gal of hydraulic fluid? Or will it likely be a bit less? Just wondering exactly how much UDT2 I’ll need to order.

Any reason to prefer UDT2 over 90wt gear oil in the front end?
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   / L4240 GST 1,000 Hour Service #13  
The capacities are generally total factory fill, and less will be drained out. I would say on the order of 1 gallon for an 11 gallon sump, but who knows. I have always planned on the factory spec and had a little new fluid left over just in case.
As far as the front axle, I have always preferred gear oil as opposed to UDT, even though both are acceptable on the Kubota machines I have owned.
   / L4240 GST 1,000 Hour Service #14  
When I changed the hydraulic fluid in my L3940 GST, I bought 12 gallons of UDT2..... I put 10.5 gallons in the case. I put UDT2 in the axle......just because I had the extra 1.5 gallons.