Fendt 722 S4 Vario hitch dampening oscillations

[Mislav]

Hello guys,
I have a problem with Fendt 722 S4 hitch (rear hydraulic arms). So when I'm driving on the road with hitch speed dampening active (hitch pushed on max top) and I hit some hole the hitch starts oscillating. A lot! And it goes more and more until I need to stop the tractor on the road to make it stop. The trick I learned is when I push blue STOP button for hitch it doesn't happen. I've tried to change draft settings all the way from 0% to 100% and it seems like oscillations are smaller on 0% which doesn't make any sense.

Is it hydraulic diaphragm accumulator? Faulty sensor for EHR? Faulty sensor for draft? Wrong constant in dampening program (can it be changed)?

Any help is more than welcome.

Mislav

 

[GFA]

Have you got the stabiliers in the correct hole for the machine . If the stabiliers are going too tight when lifted to full height this can happen.

 

[Mislav]

Yes. I have 2 other Fendts and it never happens. Also my front axle suspension starts to bounce a lot on big load on the road. I think maybe that's related. Maybe hydraulic oil accumulators are faulty? I studied it a bit and I see it has three accumulators for front axle (one is bounce and maybe that one is faulty).