Big vibrations in 4WD: what's happening?

[sevilla]

Hi everybody,
I have a problem: when in 4WD and the wheels are turned all the way I feel a major rhythmic vibration of the tractor (L3830 with 200hrs). It happens at very low speed. Never had that before. The only thing that changed is that yesterday, while plowing all that snow I got badly stuck in the sinking ground (not completely frozen) with a big iceberg/boulder just behind a front wheel and I used the differential lock probably in a very rough way. Any thoughts? Thank you very much for your expert suggestions.

 

[638]

Bent drive shaft to the front axle???

ron

 

[rbargeron]

......when in 4WD and the wheels are turned all the way I feel a major rhythmic vibration of the tractor (L3830 with 200hrs). It happens at very low speed.......

Do you hear any mechanical noises with the vibration? If there's no actual clunking, could it be that one of the front tires is rubbing when turned all the way and the front axle is tilted? On some models the tie rod can get bent a little and the tire ribs can rub on something.

 

[sevilla]

Thanks for the ideas: I do not see damage from the outside and there is no noise when the thing vibrates.

 

[rbargeron]

In your first post you mention the differential lock - the rear one, right? (there isn't a front one is there?) - the rear diff lock is robust enough to engage on the fly if needed - doubt that it would cause damage.
Another suggestion would be to raise the front wheels off the ground (using the loader or a floor jack) - with engine off and everything in neutral, and fwd disengaged, roll the front tires while turning the steering wheel each way (might need someone to hold one stopped while turning the other). Is there any binding or tight spots?

 

[mswlogo]

Could the differential lock be stuck on?

 

[sevilla]

Hi again, I did try do disengage the rear differential lock just in case but no improvement. But I noticed that more that a vibration is a bouncing back and front like if something would lift up and down the front of the tractor. A very strong bouncing. Also this happens only on paved road and as I said only in 4Wd at low speed. Reading the manual I noticed that it mention a vibration if the front pivot is not set properly but it should be checked at 600 hrs (I have only 200). Could this be the problem? Thanks again.

 

[art]

Did you check to see if the tire moved on the rim?

 

[sevilla]

Did you check to see if the tire moved on the rim?

Art, I did not check the tires on the rim: I will do it as soon as the weather will allow me and I'll post the results. Ice storm is supposed to arrive soon (western new England here). Thank you again .

 

[rdsaustintx]

Sorta kinda sounds normal.

The drivetrain binds in 4WD when turning sharp on solid ground. It can buck like a bronco if the frequency is just right and your foot starts rocking on the pedal.