T30 gearbox fault

Can any one help with a ?
I have a 2005 T30, tiptronic gearbox which struggles to engage 5th gear. It lets go of 4th then appears to hunt for 5 leaving the engine to race. It also seems slow to change down with the display showing high gear selected and the van struggling in low revs. To top this all off it has now developed a loud clunk form the engine bay which is I suspect one of the valves has dropped resulting in blow back through the intake air filter. this vehicle has only done 111550 mile and is less than 5 years old. Common occurance or am I that lucky?

Found the fault with the engine noise. Not dropped a valve as initially thought. Cam shaft lobes worn to destruction and buckets shot to bits.
New cam on order and replacement buckets to boot...
So much for vorsprung durch technic or however its spelt.
Still hopefully should give me another 100k miles of reasonably trouble free motoring.
Still got to get the gearbox diagnosed......
Has anyone come across this problem ( common fault ) or am I just lucky?

Worn cam shafts... being a PD it needs special PD grade oil... do you know if its had this?

I've a T5 with a PD engine, last oil fill cost me around £80! :aargh4:

Got to be done though.

Yeah I use recommended oil. Change every 10000 miles which is around about 12-16 weeks motoring. Still didn't expect such catastrophic failure on a 4 year old bus.... Not happy..

Apparently this is quite a common fault having done some asking around with local proffessionals...

Take care it could bite