grinding/howling noise in 4wd kubota m8950

[tumby]

Just noticed when in 4wd a noise is coming from the crown and pinion area. Anyone have any ideas of what it could be? It sounds like its running dry somewhere, have checked oil/grease etc can't see anything wrong....

 

[leonz]

Just noticed when in 4wd a noise is coming from the crown and pinion area. Anyone have any ideas of what it could be? It sounds like its running dry somewhere, have checked oil/grease etc can't see anything wrong....

if you are in very tight turn it may just be hopping/binding, how often are you greasing the frint wheel drive and propeller shaft bearings/spiders/steering yokes/main steering pins-upper and lower fittings?

If this tractor has a planetary wheel drive in the front have you checked the oil levels in the
planetary gearboxes on the front wheels?

My other question is whether you have trash underneath the tractor and do not see it?