I have a McCormick GXH45. (Hydro) After about an hour of use the hydostat oil level goes down about 1/4 of the sightglass or about 3/4 of a quart. I checked the Trans/Hyd resevoir and all the oil I had been adding in the last 2 years to the Hydro resevoir was in there. The Trans/Hyd resevoir was higher than the hydro oil level so I know it must be pressurized oil getting there. The dealer split the tractor and put fuel oil in the trans/hyd resevoir to see if any of the seals leak between resevoirs, but found no leaks. They put new seals in anyway and gave it back to me. Still have the same problem. The only line that could communicate between the two fluids is the differential lock which is operated by hydo oil. It would take two failures, the solenoid valve and the plunger for the differential lock. After running out of ideas I'm about ready to think it has to be the differential lock system. Anybody else have any similar symptoms and answers? Ideas?
Disappearing hydostat oil
- Thread starter Ben_W
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I am not familiar with this tractor(too new!). Does the three point hitch have an internally plumbed line to a lift cylinder that is inside the compartment that has the rising oil level? If so, a leak in the line or in the cylinder packing could cause the same problem. 
Soundguy
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Wow.. that system uses ATF fluid in it's hydro? What type?
Soundguy
Soundguy
Sorry so long to reply. Yes, the manual says Type A. The dealer said that any Dextron was fine to use. I had a repair done awhile back and they refilled it with Dextron. Probably Dextron lll. It made the hydro run much quieter. From what I've read Dextron is a replacement for Type A. Type A is used in Europe more than in the States.
Soundguy
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Does that have seperate oil in front gears etc?
Soundguy
Soundguy
If I understand the question: The hydrostat oil (ATF) is in the front compartment and the hydraulic/rear gear drive oil in a rear compartment. The front differential is 80/90W. The power steering uses hydrostat oil supplied by an external pump driven off the engine.
Soundguy
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- RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
Ok.. that is waht I was wondering. The atf is only for the trans / hyds.. and not the gears.
Soundguy
Soundguy
