X3 Annoying rattle and notchy gear change.

[etch]

Hi all, i have a 2005 2.0d sport with a few irratating faults, firstly i have a tinny rattle which seems to be coming from the exhaust back box area, the rattle happens if the car is labouring ie doing 30mph in 5th gear or when the load is off the near side rear wheel going around corners or islands i know 30mph in 5th is a little low but i am trying to create the fault.

The second fault is the gearbox is very stiff when i am moving from 1st to 2nd then 3rd to fourth i sometimes have to force the gear lever to get the gear and then it's very notchy, other times the gearbox is has smooth as silk i have had a new clutch etc under warranty but it is still the same, i have the BMW extended warranty on the car which expires July so i would like to get this sorted asap.

Thank you in advance for any replies.

Sean