Hi, I picked up a generally decent CASE 450C recently for $7000, figuring I could afford a few repairs getting it at that price. All is well, except now I am using it a lot and can hear a distinct worn-bearing type noise when pushing a load in the low speed setting (meaning the low setting on the steering sticks and not the hi-lo gear on the input shaft). The noise is somewhat similar to the sound of a stick shift car when driven fast in reverse. The noise vanishes when pushing the sticks forward into the high setting. Does anyone have a clear idea what this sound is likely to be (i.e. which bearing), and whether this bearing repair is possible with the transmission in the frame? I should also ask if a certain amount of this noise is normal in any way due to the low speed gearing? The machine has 5716 hours on it. Many thanks for any help!
Welcome to HEF texas450c! It's very hard to say without actually hearing your machine. If there is any problem with the transmission the suction screen will usually tell you a story.... look there first. They don't really change noise levels too much between ranges, so there may very well be something going on with it. Has it sat a while before you bought it? I have seen nasty rust issues occur on gear teeth in such situations... PS - there is not too much that can be repaired in frame, apart from brakes, anything else & it is best removed. The transmission needs to be on it's back to remove the front cover.
Thanks alrman! Yes the dozer had sat for about a year (so they told me). I guess it may be a rust type issue. I changed all hydraulic fluids though they seemed to be in good shape as far as not having water evident in them. You made reference to it, but should I assume that no different bearings are being used between hi and low speed? If that it is true then might it just be noise coming from gear teeth being rusted/pitted or just plain worn?
I can't really say that, if it was rusted, that it would create the noise you hear. I'm sorta thinking out loud When you say you replaced the all hydraulic fluids - does that include the transmission & final drive (x2) oils? Was the suction screen/filter inspected?
I did not inspect the suction screen... Will do that, thx. I replaced all other fluids but just checked the level on the final drives. The oil looked good.