Thule Dropdown Step 550 (4 Viewers)

[Cobnarowl]

Sometimes the tread appears to move slightly sideways and gets stuck as if some of the joints are wearing out.At other times it works fine.Can these joints be replaced.I'm pretty sure its not the cog/teeth problem

 

[Blaydon]

Not sure about parts, but I bought a drop down step on eBay for about £100. We had a slide out step which is really only good on a panel van. It was easy to fit even though I had to make up a mounting bracket. You could sell the old set for parts to recoup some of your money. Take care when wiring, ours currently works the wrong way, up is out and down is in - I really should go back and swap the wires round.
Just a thought