Help!! please with 9540 noise

[Basset1]

Hi hoping someone may be able to help me here or had a similar problem. I’m just about over it. So our 9540 has a clunking sort of noise really bad when you turn steering either way not to bad going straight but when you turn you could feel it right thru the tractor almost like the front wheels were binding up. Was pretty sure it was coming from the front end disconnected prop shaft was still there. Lifted front end up with loader spun up wheels no unusual noises or play all seemed ok. Drove it backward with front end in air using loader noise wasn’t there so I was pretty confident it was in the front end. Being as I work away and don’t have much time at home it was a pretty quick diagnosis and I ripped into it pulled out front axle lsd split hubs etc expecting to find something pretty obvious due to severity of noise but found nothing. Thought it may be in lsd but no obvious problem there. Everythings like brand new hub oils were spotless, diff oil was clean only found the tiniest of shiny stuff in the diff housing once everything was out. The only unusual thing I saw was the bevel gear in the left hub the one the axle goes into and the bevel gear it meshes with had what looked like 2 different tooth contact marks. Just by quick visual and feel on bearings can’t find anything wrong with them. So my question is how precise is the backlash between bevel gears? If it’s way out you’ll have dramas but a tiny bit? I havnt worked on a setup like this before so not really sure used to working on trucks. Just a bit dumbfounded to not see anything obvious. Anyway any help or advise much appreciated thanks. Also add tractor only has just over 2000 hrs on it

 

[Basset1]

Anyone got any ideas or suggestions? Has anyone seen failures in the front ends of these bigger tractors? After doing a lot of searching I see a lot of failures in the smaller tractors but none in the bigger ones.
Thanks

 

[Dustyx2]

I looked in the WSM of my M7060 and depending on position, they call for .004 to .010" or .008 to .010".
In the trouble shooting for clunk it also indicates excessive backlash as a cause. That gear certainly looks like its pattern has changed and possibly has too much backlash. I would investigate further.

 

[rbargeron]

The picture looks like high tooth-contact force - with small metal debris marks - like mashed hard foil coming off ball bearings.

If the clunk is only once per turn of the tire, its likely a bad spot in the outer hub bearings. If it's more like 10 per tire rotation it would be in the planetaries, king pins or differential bearings.

With tires off the ground there's no load on the gears - they might be seem smooth rolling. But in ground contact the front-to-back ratio difference puts enough load into the system to magnify any roughness.

As always, prompt cheerful refund if info given is bogus. Let us know what you find - Dick B

 

[kubotafreak]

My money is on hub bearings, and drop spindle bearings. They go out often with high front loader load. The giveaway is usually they will cause the seal to leak.

 

[Basset1]

Thank you for your reply’s, given me more to think about. Dick b - I would say it would have been at least 10times a rotation it clunked, I did pull one planetary out seemed fine but yet to pull out sun gears and check needle bearings. Also yet to pull out other side so I’ll keep you posted once I get all that pulled down. Also no leaking seals.

 

[rbargeron]

The bevel gears are necessarily small for compactness, and have a small contact ratio (the number of teeth actually in contact at once). Clunking often means there's a damaged tooth or two that no longer run clean under load.

The "high speed parts" running at 10x the wheel rpm are the front differential & gear shafts, including limited slip clutch pack, king pins & gears. Things slow down at the planetaries in the hubs, with fixed ring, driving sun gear and driven planet carrier turning the wheel. Do you use Kub's illustrated parts lists? The front axle is spread out over 14 panels but its all there.

Before you take the other side apart, try holding a shaft end and turning the pinion or axle - see if whatever is unhappy will reveal itself. Hope you find the clunking gun - Dick B

 

[Basset1]

The bevel gears are necessarily small for compactness, and have a small contact ratio (the number of teeth actually in contact at once). Clunking often means there's a damaged tooth or two that no longer run clean under load.

The "high speed parts" running at 10x the wheel rpm are the front differential & gear shafts, including limited slip clutch pack, king pins & gears. Things slow down at the planetaries in the hubs, with fixed ring, driving sun gear and driven planet carrier turning the wheel. Do you use Kub's illustrated parts lists? The front axle is spread out over 14 panels but its all there.

Before you take the other side apart, try holding a shaft end and turning the pinion or axle - see if whatever is unhappy will reveal itself. Hope you find the clunking gun - Dick B

I actually had it all apart already just not the planetary and have just spent a bit more time on it. Still havnt found anything obvious, tiny bit of play in a couple of bearings- 1 in centre of planetary and other in the outer part of hub where the stub comes thru to go to the wheel studs. Changing any suss ones and going to put it back together. Still at a bit of a loss I can’t see anything obvious for the noise it was making.

Also I’ve used the messicks parts diagrams they are quite helpful. Havnt used the one you linked too.
Thanks

 

[rbargeron]

Reliable parts info, whichever way you access it. Hope the cause of the clunk was in the "suss" bearings being replaced?. Dick B