Ok looks like my mate may have stripped the threads in the nut where the rear skewer goes in to.

Anyone else done this and know where to get the spares

Also is there a parts diagram available on the trek website or somewhere else.

Cheers,

Yeah i did the same. I contacted trek and got an email with diagram and part no. I then ordered part through Evans cycles and it took about 2 weeks to arrive. It cost £13 + £5 for special order. which is steep for a nut but needs must.
I have forwarded you the email i recieved from trek to save you the hassle.
Hope this helps
Gavin.

many thanks Gavin

whilst i was waiting for the part to arrive i still managed to do my damaged nut up. It was just catching on the last few treads and i used a load of locktite. you could try this. but if it wont tighten at all and the nut keeps spinning dont chance it and you’ll just have to be patient and wait for new one.