Well, pretty old one - 1991.
When there's no problem with traction, than, I think, that the steering valve simply reached it's lifetime.
It's hard to repair it, easier to replace.
The part No is 3525421200 - new, 3525421280 - refurbished.
The price - about 3300 PLN for the new, 2500 PLN for refurished.
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