I have a Komatsu D41S3 Tracked Loader in Good overall condition but after operating it for 45 min or so I start to loose steering and after a few more min will loose all directional steering. If I let this machine sit for 8 hours or so I can repeat the same steering lose. My first thought was clutches but because I can repeat every eight hours I'm leaning away from clutches. I've checked steering pump pressure and it remains constant, so my thoughts are she is bypassing pressure after warming up. Fluids and filters have been replaced and system air leaks have been examined. Your thoughts. Thanks
Maybe as fluid warms up it is thinning and bypassing a seal or something?
Probably the seals on t he steering clutches you will have to remove the clutches to re seal and check the bevel gear and top pinion bearings for looseness sometimes they will get wore and knock out the clutch seals