Howdy. I purchased a Cat D5C (S/N: 9DL0730). It has a steering issue that I am trying solve. This is my first dozer repair but I have worked on lots of automotive stuff. Symptoms: The dozer will not turn left. Turns right ok. When you apply only the left pedal the machine just comes to a complete stop. Another thing I noticed is that the machine will drift to the right when tracking straight forward. What I have done so far: I inspected the linkages to the steering control valves and they look good. I took both steering valves off and inspected the roller bearing on the end of the spool and the cam lobes. I took the valves apart and they appear to be in good condition. The oil looked clean and I didn't see anything out of the ordinary (broken springs, bad O-ring, etc). What I think is happening: I am thinking the left steering clutch is failing to release (or is totally jammed/welded solid) and only the service brake is working on that side. Maybe the hydraulic piston that disengages the steering clutch is shot? Is there anything else I should check? Is there anything else I should check before I tear it down more? Is it possible that I have multiple issues that present itself as one problem? I am on the right track?
You need to check pressure at the slave cylinders there is a tap on the outside of case by the track
Ok that sounds good. I'm starting to believe that the right side clutches are the primary culprit since it is pulling to the right whilst tracking forward.
Can you expand on what to expect if the pressure is off of what the book quotes?
If You see around 85 psi the transmission is at primary pressure. It is most likely caused by load piston orifice being plugged in transmission.