I’m looking at a IT28F that has the hydraulic fluid disappearing from the tank only to show up as an overfilled transmission. I’m thinking it’s going from the pump into the transmission. If that’s the case are there any long term issues with the transmission? I believe Cat calls for their TDTO fluid… I remember when I was in the Army their fluid was 15/40 engine oil in everything, engine transmission and hydraulic, in everything, trucks engineer equipment and tanks. Thanks in advance for your help, Russ
That was back in the “one size fits all” days (70s thru 90s). Things have changed a bit since then. The big factor is that engine oil does not contain the anti-foaming additives required for a hydraulic oil which makes it less than ideal. For your climate the recommended hydraulic oil is an SAE10W, transmission a TO-4 SAE30. Post a machine Serial Number so we can dig deeper into the oil transfer. There may be other possibilities apart from the implement pump shaft seal but not sure at the moment.
Hi Nige, I was hoping you would answer me, I read a lot of your work here, great stuff, thanks. Anyway here’s the serial number, **3CL00750** I look forward to reading what you come up with. Russ
From a brief look at the SysOp the pump appears to be the most logical route for oil from the hydraulic tank to end up in the transmission. Oil from a single hydraulic tank is used to supply implements, brakes, and steering, so the fact the oil level in the tank is going down could mean a leak in any one of those systems. The pump (see below) has 3 sections, the one closest to the transmission (#1) being for the steering, the centre one (#10) for the implements, and the outer one (#6) for the brakes. A leak from the steering section would be the obvious suspect, but don't discount the possibility that oil could be leaking through the pump stack from further upstream.
Thank you, what is your opinion about the hydro fluid in the transmission, no long term effects or problems with the transmission?
IMHO it should be fixed asap. Different viscosity oils, different additive packages all indicate it’s not good long-term for the transmission. Depending on how many hours the machine has prepare yourself for the possibility that one or more sections on the pump may require a complete rebuild or even replacement.